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android / platform / libcore / 71f2c75111e87091616f0f3b86bea6c4d345dad1 / . / src / hotspot / cpu / aarch64 / sharedRuntime_aarch64.cpp
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/*
* Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2014, 2019, Red Hat Inc. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "asm/macroAssembler.hpp"
#include "asm/macroAssembler.inline.hpp"
#include "code/debugInfoRec.hpp"
#include "code/icBuffer.hpp"
#include "code/vtableStubs.hpp"
#include "interpreter/interpreter.hpp"
#include "interpreter/interp_masm.hpp"
#include "logging/log.hpp"
#include "memory/resourceArea.hpp"
#include "oops/compiledICHolder.hpp"
#include "runtime/safepointMechanism.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/vframeArray.hpp"
#include "utilities/align.hpp"
#include "vmreg_aarch64.inline.hpp"
#ifdef COMPILER1
#include "c1/c1_Runtime1.hpp"
#endif
#if COMPILER2_OR_JVMCI
#include "adfiles/ad_aarch64.hpp"
#include "opto/runtime.hpp"
#endif
#if INCLUDE_JVMCI
#include "jvmci/jvmciJavaClasses.hpp"
#endif
#define __ masm->
const int StackAlignmentInSlots = StackAlignmentInBytes / VMRegImpl::stack_slot_size;
class SimpleRuntimeFrame {
public:
// Most of the runtime stubs have this simple frame layout.
// This class exists to make the layout shared in one place.
// Offsets are for compiler stack slots, which are jints.
enum layout {
// The frame sender code expects that rbp will be in the "natural" place and
// will override any oopMap setting for it. We must therefore force the layout
// so that it agrees with the frame sender code.
// we don't expect any arg reg save area so aarch64 asserts that
// frame::arg_reg_save_area_bytes == 0
rbp_off = 0,
rbp_off2,
return_off, return_off2,
framesize
};
};
// FIXME -- this is used by C1
class RegisterSaver {
public:
static OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors = false);
static void restore_live_registers(MacroAssembler* masm, bool restore_vectors = false);
// Offsets into the register save area
// Used by deoptimization when it is managing result register
// values on its own
static int r0_offset_in_bytes(void) { return (32 + r0->encoding()) * wordSize; }
static int reg_offset_in_bytes(Register r) { return r0_offset_in_bytes() + r->encoding() * wordSize; }
static int rmethod_offset_in_bytes(void) { return reg_offset_in_bytes(rmethod); }
static int rscratch1_offset_in_bytes(void) { return (32 + rscratch1->encoding()) * wordSize; }
static int v0_offset_in_bytes(void) { return 0; }
static int return_offset_in_bytes(void) { return (32 /* floats*/ + 31 /* gregs*/) * wordSize; }
// During deoptimization only the result registers need to be restored,
// all the other values have already been extracted.
static void restore_result_registers(MacroAssembler* masm);
// Capture info about frame layout
enum layout {
fpu_state_off = 0,
fpu_state_end = fpu_state_off + FPUStateSizeInWords - 1,
// The frame sender code expects that rfp will be in
// the "natural" place and will override any oopMap
// setting for it. We must therefore force the layout
// so that it agrees with the frame sender code.
r0_off = fpu_state_off + FPUStateSizeInWords,
rfp_off = r0_off + (RegisterImpl::number_of_registers - 2) * RegisterImpl::max_slots_per_register,
return_off = rfp_off + RegisterImpl::max_slots_per_register, // slot for return address
reg_save_size = return_off + RegisterImpl::max_slots_per_register};
};
OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors) {
#if COMPILER2_OR_JVMCI
if (save_vectors) {
// Save upper half of vector registers
int vect_words = FloatRegisterImpl::number_of_registers * FloatRegisterImpl::extra_save_slots_per_register /
VMRegImpl::slots_per_word;
additional_frame_words += vect_words;
}
#else
assert(!save_vectors, "vectors are generated only by C2 and JVMCI");
#endif
int frame_size_in_bytes = align_up(additional_frame_words * wordSize +
reg_save_size * BytesPerInt, 16);
// OopMap frame size is in compiler stack slots (jint's) not bytes or words
int frame_size_in_slots = frame_size_in_bytes / BytesPerInt;
// The caller will allocate additional_frame_words
int additional_frame_slots = additional_frame_words * wordSize / BytesPerInt;
// CodeBlob frame size is in words.
int frame_size_in_words = frame_size_in_bytes / wordSize;
*total_frame_words = frame_size_in_words;
// Save Integer and Float registers.
__ enter();
__ push_CPU_state(save_vectors);
// Set an oopmap for the call site. This oopmap will map all
// oop-registers and debug-info registers as callee-saved. This
// will allow deoptimization at this safepoint to find all possible
// debug-info recordings, as well as let GC find all oops.
OopMapSet *oop_maps = new OopMapSet();
OopMap* oop_map = new OopMap(frame_size_in_slots, 0);
for (int i = 0; i < RegisterImpl::number_of_registers; i++) {
Register r = as_Register(i);
if (r < rheapbase && r != rscratch1 && r != rscratch2) {
// SP offsets are in 4-byte words.
// Register slots are 8 bytes wide, 32 floating-point registers.
int sp_offset = RegisterImpl::max_slots_per_register * i +
FloatRegisterImpl::save_slots_per_register * FloatRegisterImpl::number_of_registers;
oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset + additional_frame_slots),
r->as_VMReg());
}
}
for (int i = 0; i < FloatRegisterImpl::number_of_registers; i++) {
FloatRegister r = as_FloatRegister(i);
int sp_offset = save_vectors ? (FloatRegisterImpl::max_slots_per_register * i) :
(FloatRegisterImpl::save_slots_per_register * i);
oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset),
r->as_VMReg());
}
return oop_map;
}
void RegisterSaver::restore_live_registers(MacroAssembler* masm, bool restore_vectors) {
#ifndef COMPILER2
assert(!restore_vectors, "vectors are generated only by C2 and JVMCI");
#endif
__ pop_CPU_state(restore_vectors);
__ leave();
}
void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
// Just restore result register. Only used by deoptimization. By
// now any callee save register that needs to be restored to a c2
// caller of the deoptee has been extracted into the vframeArray
// and will be stuffed into the c2i adapter we create for later
// restoration so only result registers need to be restored here.
// Restore fp result register
__ ldrd(v0, Address(sp, v0_offset_in_bytes()));
// Restore integer result register
__ ldr(r0, Address(sp, r0_offset_in_bytes()));
// Pop all of the register save are off the stack
__ add(sp, sp, align_up(return_offset_in_bytes(), 16));
}
// Is vector's size (in bytes) bigger than a size saved by default?
// 8 bytes vector registers are saved by default on AArch64.
bool SharedRuntime::is_wide_vector(int size) {
return size > 8;
}
size_t SharedRuntime::trampoline_size() {
return 16;
}
void SharedRuntime::generate_trampoline(MacroAssembler *masm, address destination) {
__ mov(rscratch1, destination);
__ br(rscratch1);
}
// The java_calling_convention describes stack locations as ideal slots on
// a frame with no abi restrictions. Since we must observe abi restrictions
// (like the placement of the register window) the slots must be biased by
// the following value.
static int reg2offset_in(VMReg r) {
// Account for saved rfp and lr
// This should really be in_preserve_stack_slots
return (r->reg2stack() + 4) * VMRegImpl::stack_slot_size;
}
static int reg2offset_out(VMReg r) {
return (r->reg2stack() + SharedRuntime::out_preserve_stack_slots()) * VMRegImpl::stack_slot_size;
}
// ---------------------------------------------------------------------------
// Read the array of BasicTypes from a signature, and compute where the
// arguments should go. Values in the VMRegPair regs array refer to 4-byte
// quantities. Values less than VMRegImpl::stack0 are registers, those above
// refer to 4-byte stack slots. All stack slots are based off of the stack pointer
// as framesizes are fixed.
// VMRegImpl::stack0 refers to the first slot 0(sp).
// and VMRegImpl::stack0+1 refers to the memory word 4-byes higher. Register
// up to RegisterImpl::number_of_registers) are the 64-bit
// integer registers.
// Note: the INPUTS in sig_bt are in units of Java argument words,
// which are 64-bit. The OUTPUTS are in 32-bit units.
// The Java calling convention is a "shifted" version of the C ABI.
// By skipping the first C ABI register we can call non-static jni
// methods with small numbers of arguments without having to shuffle
// the arguments at all. Since we control the java ABI we ought to at
// least get some advantage out of it.
int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
VMRegPair *regs,
int total_args_passed,
int is_outgoing) {
// Create the mapping between argument positions and
// registers.
static const Register INT_ArgReg[Argument::n_int_register_parameters_j] = {
j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7
};
static const FloatRegister FP_ArgReg[Argument::n_float_register_parameters_j] = {
j_farg0, j_farg1, j_farg2, j_farg3,
j_farg4, j_farg5, j_farg6, j_farg7
};
uint int_args = 0;
uint fp_args = 0;
uint stk_args = 0; // inc by 2 each time
for (int i = 0; i < total_args_passed; i++) {
switch (sig_bt[i]) {
case T_BOOLEAN:
case T_CHAR:
case T_BYTE:
case T_SHORT:
case T_INT:
if (int_args < Argument::n_int_register_parameters_j) {
regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
} else {
regs[i].set1(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_VOID:
// halves of T_LONG or T_DOUBLE
assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
regs[i].set_bad();
break;
case T_LONG:
assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
// fall through
case T_OBJECT:
case T_ARRAY:
case T_ADDRESS:
if (int_args < Argument::n_int_register_parameters_j) {
regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
} else {
regs[i].set2(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_FLOAT:
if (fp_args < Argument::n_float_register_parameters_j) {
regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
} else {
regs[i].set1(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_DOUBLE:
assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
if (fp_args < Argument::n_float_register_parameters_j) {
regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
} else {
regs[i].set2(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
default:
ShouldNotReachHere();
break;
}
}
return align_up(stk_args, 2);
}
// Patch the callers callsite with entry to compiled code if it exists.
static void patch_callers_callsite(MacroAssembler *masm) {
Label L;
__ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
__ cbz(rscratch1, L);
__ enter();
__ push_CPU_state();
// VM needs caller's callsite
// VM needs target method
// This needs to be a long call since we will relocate this adapter to
// the codeBuffer and it may not reach
#ifndef PRODUCT
assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
#endif
__ mov(c_rarg0, rmethod);
__ mov(c_rarg1, lr);
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
__ blr(rscratch1);
__ maybe_isb();
__ pop_CPU_state();
// restore sp
__ leave();
__ bind(L);
}
static void gen_c2i_adapter(MacroAssembler *masm,
int total_args_passed,
int comp_args_on_stack,
const BasicType *sig_bt,
const VMRegPair *regs,
Label& skip_fixup) {
// Before we get into the guts of the C2I adapter, see if we should be here
// at all. We've come from compiled code and are attempting to jump to the
// interpreter, which means the caller made a static call to get here
// (vcalls always get a compiled target if there is one). Check for a
// compiled target. If there is one, we need to patch the caller's call.
patch_callers_callsite(masm);
__ bind(skip_fixup);
int words_pushed = 0;
// Since all args are passed on the stack, total_args_passed *
// Interpreter::stackElementSize is the space we need.
int extraspace = total_args_passed * Interpreter::stackElementSize;
__ mov(r13, sp);
// stack is aligned, keep it that way
extraspace = align_up(extraspace, 2*wordSize);
if (extraspace)
__ sub(sp, sp, extraspace);
// Now write the args into the outgoing interpreter space
for (int i = 0; i < total_args_passed; i++) {
if (sig_bt[i] == T_VOID) {
assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
continue;
}
// offset to start parameters
int st_off = (total_args_passed - i - 1) * Interpreter::stackElementSize;
int next_off = st_off - Interpreter::stackElementSize;
// Say 4 args:
// i st_off
// 0 32 T_LONG
// 1 24 T_VOID
// 2 16 T_OBJECT
// 3 8 T_BOOL
// - 0 return address
//
// However to make thing extra confusing. Because we can fit a Java long/double in
// a single slot on a 64 bt vm and it would be silly to break them up, the interpreter
// leaves one slot empty and only stores to a single slot. In this case the
// slot that is occupied is the T_VOID slot. See I said it was confusing.
VMReg r_1 = regs[i].first();
VMReg r_2 = regs[i].second();
if (!r_1->is_valid()) {
assert(!r_2->is_valid(), "");
continue;
}
if (r_1->is_stack()) {
// memory to memory use rscratch1
int ld_off = (r_1->reg2stack() * VMRegImpl::stack_slot_size
+ extraspace
+ words_pushed * wordSize);
if (!r_2->is_valid()) {
// sign extend??
__ ldrw(rscratch1, Address(sp, ld_off));
__ str(rscratch1, Address(sp, st_off));
} else {
__ ldr(rscratch1, Address(sp, ld_off));
// Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
// T_DOUBLE and T_LONG use two slots in the interpreter
if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
// ld_off == LSW, ld_off+wordSize == MSW
// st_off == MSW, next_off == LSW
__ str(rscratch1, Address(sp, next_off));
#ifdef ASSERT
// Overwrite the unused slot with known junk
__ mov(rscratch1, (uint64_t)0xdeadffffdeadaaaaull);
__ str(rscratch1, Address(sp, st_off));
#endif /* ASSERT */
} else {
__ str(rscratch1, Address(sp, st_off));
}
}
} else if (r_1->is_Register()) {
Register r = r_1->as_Register();
if (!r_2->is_valid()) {
// must be only an int (or less ) so move only 32bits to slot
// why not sign extend??
__ str(r, Address(sp, st_off));
} else {
// Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
// T_DOUBLE and T_LONG use two slots in the interpreter
if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
// jlong/double in gpr
#ifdef ASSERT
__ mov(rscratch1, (uint64_t)0xdeadffffdeadaaabull);
__ str(rscratch1, Address(sp, st_off));
#endif /* ASSERT */
__ str(r, Address(sp, next_off));
} else {
__ str(r, Address(sp, st_off));
}
}
} else {
assert(r_1->is_FloatRegister(), "");
if (!r_2->is_valid()) {
// only a float use just part of the slot
__ strs(r_1->as_FloatRegister(), Address(sp, st_off));
} else {
#ifdef ASSERT
// Overwrite the unused slot with known junk
__ mov(rscratch1, (uint64_t)0xdeadffffdeadaaacull);
__ str(rscratch1, Address(sp, st_off));
#endif /* ASSERT */
__ strd(r_1->as_FloatRegister(), Address(sp, next_off));
}
}
}
__ mov(esp, sp); // Interp expects args on caller's expression stack
__ ldr(rscratch1, Address(rmethod, in_bytes(Method::interpreter_entry_offset())));
__ br(rscratch1);
}
void SharedRuntime::gen_i2c_adapter(MacroAssembler *masm,
int total_args_passed,
int comp_args_on_stack,
const BasicType *sig_bt,
const VMRegPair *regs) {
// Note: r13 contains the senderSP on entry. We must preserve it since
// we may do a i2c -> c2i transition if we lose a race where compiled
// code goes non-entrant while we get args ready.
// In addition we use r13 to locate all the interpreter args because
// we must align the stack to 16 bytes.
// Adapters are frameless.
// An i2c adapter is frameless because the *caller* frame, which is
// interpreted, routinely repairs its own esp (from
// interpreter_frame_last_sp), even if a callee has modified the
// stack pointer. It also recalculates and aligns sp.
// A c2i adapter is frameless because the *callee* frame, which is
// interpreted, routinely repairs its caller's sp (from sender_sp,
// which is set up via the senderSP register).
// In other words, if *either* the caller or callee is interpreted, we can
// get the stack pointer repaired after a call.
// This is why c2i and i2c adapters cannot be indefinitely composed.
// In particular, if a c2i adapter were to somehow call an i2c adapter,
// both caller and callee would be compiled methods, and neither would
// clean up the stack pointer changes performed by the two adapters.
// If this happens, control eventually transfers back to the compiled
// caller, but with an uncorrected stack, causing delayed havoc.
if (VerifyAdapterCalls &&
(Interpreter::code() != NULL || StubRoutines::code1() != NULL)) {
#if 0
// So, let's test for cascading c2i/i2c adapters right now.
// assert(Interpreter::contains($return_addr) ||
// StubRoutines::contains($return_addr),
// "i2c adapter must return to an interpreter frame");
__ block_comment("verify_i2c { ");
Label L_ok;
if (Interpreter::code() != NULL)
range_check(masm, rax, r11,
Interpreter::code()->code_start(), Interpreter::code()->code_end(),
L_ok);
if (StubRoutines::code1() != NULL)
range_check(masm, rax, r11,
StubRoutines::code1()->code_begin(), StubRoutines::code1()->code_end(),
L_ok);
if (StubRoutines::code2() != NULL)
range_check(masm, rax, r11,
StubRoutines::code2()->code_begin(), StubRoutines::code2()->code_end(),
L_ok);
const char* msg = "i2c adapter must return to an interpreter frame";
__ block_comment(msg);
__ stop(msg);
__ bind(L_ok);
__ block_comment("} verify_i2ce ");
#endif
}
// Cut-out for having no stack args.
int comp_words_on_stack = align_up(comp_args_on_stack*VMRegImpl::stack_slot_size, wordSize)>>LogBytesPerWord;
if (comp_args_on_stack) {
__ sub(rscratch1, sp, comp_words_on_stack * wordSize);
__ andr(sp, rscratch1, -16);
}
// Will jump to the compiled code just as if compiled code was doing it.
// Pre-load the register-jump target early, to schedule it better.
__ ldr(rscratch1, Address(rmethod, in_bytes(Method::from_compiled_offset())));
#if INCLUDE_JVMCI
if (EnableJVMCI || UseAOT) {
// check if this call should be routed towards a specific entry point
__ ldr(rscratch2, Address(rthread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())));
Label no_alternative_target;
__ cbz(rscratch2, no_alternative_target);
__ mov(rscratch1, rscratch2);
__ str(zr, Address(rthread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())));
__ bind(no_alternative_target);
}
#endif // INCLUDE_JVMCI
// Now generate the shuffle code.
for (int i = 0; i < total_args_passed; i++) {
if (sig_bt[i] == T_VOID) {
assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
continue;
}
// Pick up 0, 1 or 2 words from SP+offset.
assert(!regs[i].second()->is_valid() || regs[i].first()->next() == regs[i].second(),
"scrambled load targets?");
// Load in argument order going down.
int ld_off = (total_args_passed - i - 1)*Interpreter::stackElementSize;
// Point to interpreter value (vs. tag)
int next_off = ld_off - Interpreter::stackElementSize;
//
//
//
VMReg r_1 = regs[i].first();
VMReg r_2 = regs[i].second();
if (!r_1->is_valid()) {
assert(!r_2->is_valid(), "");
continue;
}
if (r_1->is_stack()) {
// Convert stack slot to an SP offset (+ wordSize to account for return address )
int st_off = regs[i].first()->reg2stack()*VMRegImpl::stack_slot_size;
if (!r_2->is_valid()) {
// sign extend???
__ ldrsw(rscratch2, Address(esp, ld_off));
__ str(rscratch2, Address(sp, st_off));
} else {
//
// We are using two optoregs. This can be either T_OBJECT,
// T_ADDRESS, T_LONG, or T_DOUBLE the interpreter allocates
// two slots but only uses one for thr T_LONG or T_DOUBLE case
// So we must adjust where to pick up the data to match the
// interpreter.
//
// Interpreter local[n] == MSW, local[n+1] == LSW however locals
// are accessed as negative so LSW is at LOW address
// ld_off is MSW so get LSW
const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
next_off : ld_off;
__ ldr(rscratch2, Address(esp, offset));
// st_off is LSW (i.e. reg.first())
__ str(rscratch2, Address(sp, st_off));
}
} else if (r_1->is_Register()) { // Register argument
Register r = r_1->as_Register();
if (r_2->is_valid()) {
//
// We are using two VMRegs. This can be either T_OBJECT,
// T_ADDRESS, T_LONG, or T_DOUBLE the interpreter allocates
// two slots but only uses one for thr T_LONG or T_DOUBLE case
// So we must adjust where to pick up the data to match the
// interpreter.
const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
next_off : ld_off;
// this can be a misaligned move
__ ldr(r, Address(esp, offset));
} else {
// sign extend and use a full word?
__ ldrw(r, Address(esp, ld_off));
}
} else {
if (!r_2->is_valid()) {
__ ldrs(r_1->as_FloatRegister(), Address(esp, ld_off));
} else {
__ ldrd(r_1->as_FloatRegister(), Address(esp, next_off));
}
}
}
// 6243940 We might end up in handle_wrong_method if
// the callee is deoptimized as we race thru here. If that
// happens we don't want to take a safepoint because the
// caller frame will look interpreted and arguments are now
// "compiled" so it is much better to make this transition
// invisible to the stack walking code. Unfortunately if
// we try and find the callee by normal means a safepoint
// is possible. So we stash the desired callee in the thread
// and the vm will find there should this case occur.
__ str(rmethod, Address(rthread, JavaThread::callee_target_offset()));
__ br(rscratch1);
}
// ---------------------------------------------------------------
AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
int total_args_passed,
int comp_args_on_stack,
const BasicType *sig_bt,
const VMRegPair *regs,
AdapterFingerPrint* fingerprint) {
address i2c_entry = __ pc();
gen_i2c_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs);
address c2i_unverified_entry = __ pc();
Label skip_fixup;
Label ok;
Register holder = rscratch2;
Register receiver = j_rarg0;
Register tmp = r10; // A call-clobbered register not used for arg passing
// -------------------------------------------------------------------------
// Generate a C2I adapter. On entry we know rmethod holds the Method* during calls
// to the interpreter. The args start out packed in the compiled layout. They
// need to be unpacked into the interpreter layout. This will almost always
// require some stack space. We grow the current (compiled) stack, then repack
// the args. We finally end in a jump to the generic interpreter entry point.
// On exit from the interpreter, the interpreter will restore our SP (lest the
// compiled code, which relys solely on SP and not FP, get sick).
{
__ block_comment("c2i_unverified_entry {");
__ load_klass(rscratch1, receiver);
__ ldr(tmp, Address(holder, CompiledICHolder::holder_klass_offset()));
__ cmp(rscratch1, tmp);
__ ldr(rmethod, Address(holder, CompiledICHolder::holder_metadata_offset()));
__ br(Assembler::EQ, ok);
__ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
__ bind(ok);
// Method might have been compiled since the call site was patched to
// interpreted; if that is the case treat it as a miss so we can get
// the call site corrected.
__ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
__ cbz(rscratch1, skip_fixup);
__ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
__ block_comment("} c2i_unverified_entry");
}
address c2i_entry = __ pc();
gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
__ flush();
return AdapterHandlerLibrary::new_entry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry);
}
int SharedRuntime::c_calling_convention(const BasicType *sig_bt,
VMRegPair *regs,
VMRegPair *regs2,
int total_args_passed) {
assert(regs2 == NULL, "not needed on AArch64");
// We return the amount of VMRegImpl stack slots we need to reserve for all
// the arguments NOT counting out_preserve_stack_slots.
static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
c_rarg0, c_rarg1, c_rarg2, c_rarg3, c_rarg4, c_rarg5, c_rarg6, c_rarg7
};
static const FloatRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
c_farg0, c_farg1, c_farg2, c_farg3,
c_farg4, c_farg5, c_farg6, c_farg7
};
uint int_args = 0;
uint fp_args = 0;
uint stk_args = 0; // inc by 2 each time
for (int i = 0; i < total_args_passed; i++) {
switch (sig_bt[i]) {
case T_BOOLEAN:
case T_CHAR:
case T_BYTE:
case T_SHORT:
case T_INT:
if (int_args < Argument::n_int_register_parameters_c) {
regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
} else {
regs[i].set1(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_LONG:
assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
// fall through
case T_OBJECT:
case T_ARRAY:
case T_ADDRESS:
case T_METADATA:
if (int_args < Argument::n_int_register_parameters_c) {
regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
} else {
regs[i].set2(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_FLOAT:
if (fp_args < Argument::n_float_register_parameters_c) {
regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
} else {
regs[i].set1(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_DOUBLE:
assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
if (fp_args < Argument::n_float_register_parameters_c) {
regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
} else {
regs[i].set2(VMRegImpl::stack2reg(stk_args));
stk_args += 2;
}
break;
case T_VOID: // Halves of longs and doubles
assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
regs[i].set_bad();
break;
default:
ShouldNotReachHere();
break;
}
}
return stk_args;
}
// On 64 bit we will store integer like items to the stack as
// 64 bits items (sparc abi) even though java would only store
// 32bits for a parameter. On 32bit it will simply be 32 bits
// So this routine will do 32->32 on 32bit and 32->64 on 64bit
static void move32_64(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
// stack to stack
__ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
__ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
} else {
// stack to reg
__ ldrsw(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
}
} else if (dst.first()->is_stack()) {
// reg to stack
// Do we really have to sign extend???
// __ movslq(src.first()->as_Register(), src.first()->as_Register());
__ str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
} else {
if (dst.first() != src.first()) {
__ sxtw(dst.first()->as_Register(), src.first()->as_Register());
}
}
}
// An oop arg. Must pass a handle not the oop itself
static void object_move(MacroAssembler* masm,
OopMap* map,
int oop_handle_offset,
int framesize_in_slots,
VMRegPair src,
VMRegPair dst,
bool is_receiver,
int* receiver_offset) {
// must pass a handle. First figure out the location we use as a handle
Register rHandle = dst.first()->is_stack() ? rscratch2 : dst.first()->as_Register();
// See if oop is NULL if it is we need no handle
if (src.first()->is_stack()) {
// Oop is already on the stack as an argument
int offset_in_older_frame = src.first()->reg2stack() + SharedRuntime::out_preserve_stack_slots();
map->set_oop(VMRegImpl::stack2reg(offset_in_older_frame + framesize_in_slots));
if (is_receiver) {
*receiver_offset = (offset_in_older_frame + framesize_in_slots) * VMRegImpl::stack_slot_size;
}
__ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
__ lea(rHandle, Address(rfp, reg2offset_in(src.first())));
// conditionally move a NULL
__ cmp(rscratch1, zr);
__ csel(rHandle, zr, rHandle, Assembler::EQ);
} else {
// Oop is in an a register we must store it to the space we reserve
// on the stack for oop_handles and pass a handle if oop is non-NULL
const Register rOop = src.first()->as_Register();
int oop_slot;
if (rOop == j_rarg0)
oop_slot = 0;
else if (rOop == j_rarg1)
oop_slot = 1;
else if (rOop == j_rarg2)
oop_slot = 2;
else if (rOop == j_rarg3)
oop_slot = 3;
else if (rOop == j_rarg4)
oop_slot = 4;
else if (rOop == j_rarg5)
oop_slot = 5;
else if (rOop == j_rarg6)
oop_slot = 6;
else {
assert(rOop == j_rarg7, "wrong register");
oop_slot = 7;
}
oop_slot = oop_slot * VMRegImpl::slots_per_word + oop_handle_offset;
int offset = oop_slot*VMRegImpl::stack_slot_size;
map->set_oop(VMRegImpl::stack2reg(oop_slot));
// Store oop in handle area, may be NULL
__ str(rOop, Address(sp, offset));
if (is_receiver) {
*receiver_offset = offset;
}
__ cmp(rOop, zr);
__ lea(rHandle, Address(sp, offset));
// conditionally move a NULL
__ csel(rHandle, zr, rHandle, Assembler::EQ);
}
// If arg is on the stack then place it otherwise it is already in correct reg.
if (dst.first()->is_stack()) {
__ str(rHandle, Address(sp, reg2offset_out(dst.first())));
}
}
// A float arg may have to do float reg int reg conversion
static void float_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
assert(src.first()->is_stack() && dst.first()->is_stack() ||
src.first()->is_reg() && dst.first()->is_reg(), "Unexpected error");
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
__ ldrw(rscratch1, Address(rfp, reg2offset_in(src.first())));
__ strw(rscratch1, Address(sp, reg2offset_out(dst.first())));
} else {
ShouldNotReachHere();
}
} else if (src.first() != dst.first()) {
if (src.is_single_phys_reg() && dst.is_single_phys_reg())
__ fmovs(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
else
ShouldNotReachHere();
}
}
// A long move
static void long_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
// stack to stack
__ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
__ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
} else {
// stack to reg
__ ldr(dst.first()->as_Register(), Address(rfp, reg2offset_in(src.first())));
}
} else if (dst.first()->is_stack()) {
// reg to stack
// Do we really have to sign extend???
// __ movslq(src.first()->as_Register(), src.first()->as_Register());
__ str(src.first()->as_Register(), Address(sp, reg2offset_out(dst.first())));
} else {
if (dst.first() != src.first()) {
__ mov(dst.first()->as_Register(), src.first()->as_Register());
}
}
}
// A double move
static void double_move(MacroAssembler* masm, VMRegPair src, VMRegPair dst) {
assert(src.first()->is_stack() && dst.first()->is_stack() ||
src.first()->is_reg() && dst.first()->is_reg(), "Unexpected error");
if (src.first()->is_stack()) {
if (dst.first()->is_stack()) {
__ ldr(rscratch1, Address(rfp, reg2offset_in(src.first())));
__ str(rscratch1, Address(sp, reg2offset_out(dst.first())));
} else {
ShouldNotReachHere();
}
} else if (src.first() != dst.first()) {
if (src.is_single_phys_reg() && dst.is_single_phys_reg())
__ fmovd(dst.first()->as_FloatRegister(), src.first()->as_FloatRegister());
else
ShouldNotReachHere();
}
}
void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
// We always ignore the frame_slots arg and just use the space just below frame pointer
// which by this time is free to use
switch (ret_type) {
case T_FLOAT:
__ strs(v0, Address(rfp, -wordSize));
break;
case T_DOUBLE:
__ strd(v0, Address(rfp, -wordSize));
break;
case T_VOID: break;
default: {
__ str(r0, Address(rfp, -wordSize));
}
}
}
void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
// We always ignore the frame_slots arg and just use the space just below frame pointer
// which by this time is free to use
switch (ret_type) {
case T_FLOAT:
__ ldrs(v0, Address(rfp, -wordSize));
break;
case T_DOUBLE:
__ ldrd(v0, Address(rfp, -wordSize));
break;
case T_VOID: break;
default: {
__ ldr(r0, Address(rfp, -wordSize));
}
}
}
static void save_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
RegSet x;
for ( int i = first_arg ; i < arg_count ; i++ ) {
if (args[i].first()->is_Register()) {
x = x + args[i].first()->as_Register();
} else if (args[i].first()->is_FloatRegister()) {
__ strd(args[i].first()->as_FloatRegister(), Address(__ pre(sp, -2 * wordSize)));
}
}
__ push(x, sp);
}
static void restore_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
RegSet x;
for ( int i = first_arg ; i < arg_count ; i++ ) {
if (args[i].first()->is_Register()) {
x = x + args[i].first()->as_Register();
} else {
;
}
}
__ pop(x, sp);
for ( int i = arg_count - 1 ; i >= first_arg ; i-- ) {
if (args[i].first()->is_Register()) {
;
} else if (args[i].first()->is_FloatRegister()) {
__ ldrd(args[i].first()->as_FloatRegister(), Address(__ post(sp, 2 * wordSize)));
}
}
}
// Check GCLocker::needs_gc and enter the runtime if it's true. This
// keeps a new JNI critical region from starting until a GC has been
// forced. Save down any oops in registers and describe them in an
// OopMap.
static void check_needs_gc_for_critical_native(MacroAssembler* masm,
int stack_slots,
int total_c_args,
int total_in_args,
int arg_save_area,
OopMapSet* oop_maps,
VMRegPair* in_regs,
BasicType* in_sig_bt) { Unimplemented(); }
// Unpack an array argument into a pointer to the body and the length
// if the array is non-null, otherwise pass 0 for both.
static void unpack_array_argument(MacroAssembler* masm, VMRegPair reg, BasicType in_elem_type, VMRegPair body_arg, VMRegPair length_arg) { Unimplemented(); }
class ComputeMoveOrder: public StackObj {
class MoveOperation: public ResourceObj {
friend class ComputeMoveOrder;
private:
VMRegPair _src;
VMRegPair _dst;
int _src_index;
int _dst_index;
bool _processed;
MoveOperation* _next;
MoveOperation* _prev;
static int get_id(VMRegPair r) { Unimplemented(); return 0; }
public:
MoveOperation(int src_index, VMRegPair src, int dst_index, VMRegPair dst):
_src(src)
, _dst(dst)
, _src_index(src_index)
, _dst_index(dst_index)
, _processed(false)
, _next(NULL)
, _prev(NULL) { Unimplemented(); }
VMRegPair src() const { Unimplemented(); return _src; }
int src_id() const { Unimplemented(); return 0; }
int src_index() const { Unimplemented(); return 0; }
VMRegPair dst() const { Unimplemented(); return _src; }
void set_dst(int i, VMRegPair dst) { Unimplemented(); }
int dst_index() const { Unimplemented(); return 0; }
int dst_id() const { Unimplemented(); return 0; }
MoveOperation* next() const { Unimplemented(); return 0; }
MoveOperation* prev() const { Unimplemented(); return 0; }
void set_processed() { Unimplemented(); }
bool is_processed() const { Unimplemented(); return 0; }
// insert
void break_cycle(VMRegPair temp_register) { Unimplemented(); }
void link(GrowableArray<MoveOperation*>& killer) { Unimplemented(); }
};
private:
GrowableArray<MoveOperation*> edges;
public:
ComputeMoveOrder(int total_in_args, VMRegPair* in_regs, int total_c_args, VMRegPair* out_regs,
BasicType* in_sig_bt, GrowableArray<int>& arg_order, VMRegPair tmp_vmreg) { Unimplemented(); }
// Collected all the move operations
void add_edge(int src_index, VMRegPair src, int dst_index, VMRegPair dst) { Unimplemented(); }
// Walk the edges breaking cycles between moves. The result list
// can be walked in order to produce the proper set of loads
GrowableArray<MoveOperation*>* get_store_order(VMRegPair temp_register) { Unimplemented(); return 0; }
};
static void rt_call(MacroAssembler* masm, address dest) {
CodeBlob *cb = CodeCache::find_blob(dest);
if (cb) {
__ far_call(RuntimeAddress(dest));
} else {
__ lea(rscratch1, RuntimeAddress(dest));
__ blr(rscratch1);
__ maybe_isb();
}
}
static void verify_oop_args(MacroAssembler* masm,
const methodHandle& method,
const BasicType* sig_bt,
const VMRegPair* regs) {
Register temp_reg = r19; // not part of any compiled calling seq
if (VerifyOops) {
for (int i = 0; i < method->size_of_parameters(); i++) {
if (sig_bt[i] == T_OBJECT ||
sig_bt[i] == T_ARRAY) {
VMReg r = regs[i].first();
assert(r->is_valid(), "bad oop arg");
if (r->is_stack()) {
__ ldr(temp_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
__ verify_oop(temp_reg);
} else {
__ verify_oop(r->as_Register());
}
}
}
}
}
static void gen_special_dispatch(MacroAssembler* masm,
const methodHandle& method,
const BasicType* sig_bt,
const VMRegPair* regs) {
verify_oop_args(masm, method, sig_bt, regs);
vmIntrinsics::ID iid = method->intrinsic_id();
// Now write the args into the outgoing interpreter space
bool has_receiver = false;
Register receiver_reg = noreg;
int member_arg_pos = -1;
Register member_reg = noreg;
int ref_kind = MethodHandles::signature_polymorphic_intrinsic_ref_kind(iid);
if (ref_kind != 0) {
member_arg_pos = method->size_of_parameters() - 1; // trailing MemberName argument
member_reg = r19; // known to be free at this point
has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);
} else if (iid == vmIntrinsics::_invokeBasic) {
has_receiver = true;
} else {
fatal("unexpected intrinsic id %d", iid);
}
if (member_reg != noreg) {
// Load the member_arg into register, if necessary.
SharedRuntime::check_member_name_argument_is_last_argument(method, sig_bt, regs);
VMReg r = regs[member_arg_pos].first();
if (r->is_stack()) {
__ ldr(member_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
} else {
// no data motion is needed
member_reg = r->as_Register();
}
}
if (has_receiver) {
// Make sure the receiver is loaded into a register.
assert(method->size_of_parameters() > 0, "oob");
assert(sig_bt[0] == T_OBJECT, "receiver argument must be an object");
VMReg r = regs[0].first();
assert(r->is_valid(), "bad receiver arg");
if (r->is_stack()) {
// Porting note: This assumes that compiled calling conventions always
// pass the receiver oop in a register. If this is not true on some
// platform, pick a temp and load the receiver from stack.
fatal("receiver always in a register");
receiver_reg = r2; // known to be free at this point
__ ldr(receiver_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
} else {
// no data motion is needed
receiver_reg = r->as_Register();
}
}
// Figure out which address we are really jumping to:
MethodHandles::generate_method_handle_dispatch(masm, iid,
receiver_reg, member_reg, /*for_compiler_entry:*/ true);
}
// ---------------------------------------------------------------------------
// Generate a native wrapper for a given method. The method takes arguments
// in the Java compiled code convention, marshals them to the native
// convention (handlizes oops, etc), transitions to native, makes the call,
// returns to java state (possibly blocking), unhandlizes any result and
// returns.
//
// Critical native functions are a shorthand for the use of
// GetPrimtiveArrayCritical and disallow the use of any other JNI
// functions. The wrapper is expected to unpack the arguments before
// passing them to the callee and perform checks before and after the
// native call to ensure that they GCLocker
// lock_critical/unlock_critical semantics are followed. Some other
// parts of JNI setup are skipped like the tear down of the JNI handle
// block and the check for pending exceptions it's impossible for them
// to be thrown.
//
// They are roughly structured like this:
// if (GCLocker::needs_gc())
// SharedRuntime::block_for_jni_critical();
// tranistion to thread_in_native
// unpack arrray arguments and call native entry point
// check for safepoint in progress
// check if any thread suspend flags are set
// call into JVM and possible unlock the JNI critical
// if a GC was suppressed while in the critical native.
// transition back to thread_in_Java
// return to caller
//
nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
const methodHandle& method,
int compile_id,
BasicType* in_sig_bt,
VMRegPair* in_regs,
BasicType ret_type,
address critical_entry) {
if (method->is_method_handle_intrinsic()) {
vmIntrinsics::ID iid = method->intrinsic_id();
intptr_t start = (intptr_t)__ pc();
int vep_offset = ((intptr_t)__ pc()) - start;
// First instruction must be a nop as it may need to be patched on deoptimisation
__ nop();
gen_special_dispatch(masm,
method,
in_sig_bt,
in_regs);
int frame_complete = ((intptr_t)__ pc()) - start; // not complete, period
__ flush();
int stack_slots = SharedRuntime::out_preserve_stack_slots(); // no out slots at all, actually
return nmethod::new_native_nmethod(method,
compile_id,
masm->code(),
vep_offset,
frame_complete,
stack_slots / VMRegImpl::slots_per_word,
in_ByteSize(-1),
in_ByteSize(-1),
(OopMapSet*)NULL);
}
bool is_critical_native = true;
address native_func = critical_entry;
if (native_func == NULL) {
native_func = method->native_function();
is_critical_native = false;
}
assert(native_func != NULL, "must have function");
// An OopMap for lock (and class if static)
OopMapSet *oop_maps = new OopMapSet();
intptr_t start = (intptr_t)__ pc();
// We have received a description of where all the java arg are located
// on entry to the wrapper. We need to convert these args to where
// the jni function will expect them. To figure out where they go
// we convert the java signature to a C signature by inserting
// the hidden arguments as arg[0] and possibly arg[1] (static method)
const int total_in_args = method->size_of_parameters();
int total_c_args = total_in_args;
if (!is_critical_native) {
total_c_args += 1;
if (method->is_static()) {
total_c_args++;
}
} else {
for (int i = 0; i < total_in_args; i++) {
if (in_sig_bt[i] == T_ARRAY) {
total_c_args++;
}
}
}
BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);
VMRegPair* out_regs = NEW_RESOURCE_ARRAY(VMRegPair, total_c_args);
BasicType* in_elem_bt = NULL;
int argc = 0;
if (!is_critical_native) {
out_sig_bt[argc++] = T_ADDRESS;
if (method->is_static()) {
out_sig_bt[argc++] = T_OBJECT;
}
for (int i = 0; i < total_in_args ; i++ ) {
out_sig_bt[argc++] = in_sig_bt[i];
}
} else {
Thread* THREAD = Thread::current();
in_elem_bt = NEW_RESOURCE_ARRAY(BasicType, total_in_args);
SignatureStream ss(method->signature());
for (int i = 0; i < total_in_args ; i++ ) {
if (in_sig_bt[i] == T_ARRAY) {
// Arrays are passed as int, elem* pair
out_sig_bt[argc++] = T_INT;
out_sig_bt[argc++] = T_ADDRESS;
Symbol* atype = ss.as_symbol(CHECK_NULL);
const char* at = atype->as_C_string();
if (strlen(at) == 2) {
assert(at[0] == '[', "must be");
switch (at[1]) {
case 'B': in_elem_bt[i] = T_BYTE; break;
case 'C': in_elem_bt[i] = T_CHAR; break;
case 'D': in_elem_bt[i] = T_DOUBLE; break;
case 'F': in_elem_bt[i] = T_FLOAT; break;
case 'I': in_elem_bt[i] = T_INT; break;
case 'J': in_elem_bt[i] = T_LONG; break;
case 'S': in_elem_bt[i] = T_SHORT; break;
case 'Z': in_elem_bt[i] = T_BOOLEAN; break;
default: ShouldNotReachHere();
}
}
} else {
out_sig_bt[argc++] = in_sig_bt[i];
in_elem_bt[i] = T_VOID;
}
if (in_sig_bt[i] != T_VOID) {
assert(in_sig_bt[i] == ss.type(), "must match");
ss.next();
}
}
}
// Now figure out where the args must be stored and how much stack space
// they require.
int out_arg_slots;
out_arg_slots = c_calling_convention(out_sig_bt, out_regs, NULL, total_c_args);
// Compute framesize for the wrapper. We need to handlize all oops in
// incoming registers
// Calculate the total number of stack slots we will need.
// First count the abi requirement plus all of the outgoing args
int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;
// Now the space for the inbound oop handle area
int total_save_slots = 8 * VMRegImpl::slots_per_word; // 8 arguments passed in registers
if (is_critical_native) {
// Critical natives may have to call out so they need a save area
// for register arguments.
int double_slots = 0;
int single_slots = 0;
for ( int i = 0; i < total_in_args; i++) {
if (in_regs[i].first()->is_Register()) {
const Register reg = in_regs[i].first()->as_Register();
switch (in_sig_bt[i]) {
case T_BOOLEAN:
case T_BYTE:
case T_SHORT:
case T_CHAR:
case T_INT: single_slots++; break;
case T_ARRAY: // specific to LP64 (7145024)
case T_LONG: double_slots++; break;
default: ShouldNotReachHere();
}
} else if (in_regs[i].first()->is_FloatRegister()) {
ShouldNotReachHere();
}
}
total_save_slots = double_slots * 2 + single_slots;
// align the save area
if (double_slots != 0) {
stack_slots = align_up(stack_slots, 2);
}
}
int oop_handle_offset = stack_slots;
stack_slots += total_save_slots;
// Now any space we need for handlizing a klass if static method
int klass_slot_offset = 0;
int klass_offset = -1;
int lock_slot_offset = 0;
bool is_static = false;
if (method->is_static()) {
klass_slot_offset = stack_slots;
stack_slots += VMRegImpl::slots_per_word;
klass_offset = klass_slot_offset * VMRegImpl::stack_slot_size;
is_static = true;
}
// Plus a lock if needed
if (method->is_synchronized()) {
lock_slot_offset = stack_slots;
stack_slots += VMRegImpl::slots_per_word;
}
// Now a place (+2) to save return values or temp during shuffling
// + 4 for return address (which we own) and saved rfp
stack_slots += 6;
// Ok The space we have allocated will look like:
//
//
// FP-> | |
// |---------------------|
// | 2 slots for moves |
// |---------------------|
// | lock box (if sync) |
// |---------------------| <- lock_slot_offset
// | klass (if static) |
// |---------------------| <- klass_slot_offset
// | oopHandle area |
// |---------------------| <- oop_handle_offset (8 java arg registers)
// | outbound memory |
// | based arguments |
// | |
// |---------------------|
// | |
// SP-> | out_preserved_slots |
//
//
// Now compute actual number of stack words we need rounding to make
// stack properly aligned.
stack_slots = align_up(stack_slots, StackAlignmentInSlots);
int stack_size = stack_slots * VMRegImpl::stack_slot_size;
// First thing make an ic check to see if we should even be here
// We are free to use all registers as temps without saving them and
// restoring them except rfp. rfp is the only callee save register
// as far as the interpreter and the compiler(s) are concerned.
const Register ic_reg = rscratch2;
const Register receiver = j_rarg0;
Label hit;
Label exception_pending;
assert_different_registers(ic_reg, receiver, rscratch1);
__ verify_oop(receiver);
__ cmp_klass(receiver, ic_reg, rscratch1);
__ br(Assembler::EQ, hit);
__ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
// Verified entry point must be aligned
__ align(8);
__ bind(hit);
int vep_offset = ((intptr_t)__ pc()) - start;
// If we have to make this method not-entrant we'll overwrite its
// first instruction with a jump. For this action to be legal we
// must ensure that this first instruction is a B, BL, NOP, BKPT,
// SVC, HVC, or SMC. Make it a NOP.
__ nop();
// Generate stack overflow check
if (UseStackBanging) {
__ bang_stack_with_offset(JavaThread::stack_shadow_zone_size());
} else {
Unimplemented();
}
// Generate a new frame for the wrapper.
__ enter();
// -2 because return address is already present and so is saved rfp
__ sub(sp, sp, stack_size - 2*wordSize);
// Frame is now completed as far as size and linkage.
int frame_complete = ((intptr_t)__ pc()) - start;
// We use r20 as the oop handle for the receiver/klass
// It is callee save so it survives the call to native
const Register oop_handle_reg = r20;
if (is_critical_native) {
check_needs_gc_for_critical_native(masm, stack_slots, total_c_args, total_in_args,
oop_handle_offset, oop_maps, in_regs, in_sig_bt);
}
//
// We immediately shuffle the arguments so that any vm call we have to
// make from here on out (sync slow path, jvmti, etc.) we will have
// captured the oops from our caller and have a valid oopMap for
// them.
// -----------------
// The Grand Shuffle
// The Java calling convention is either equal (linux) or denser (win64) than the
// c calling convention. However the because of the jni_env argument the c calling
// convention always has at least one more (and two for static) arguments than Java.
// Therefore if we move the args from java -> c backwards then we will never have
// a register->register conflict and we don't have to build a dependency graph
// and figure out how to break any cycles.
//
// Record esp-based slot for receiver on stack for non-static methods
int receiver_offset = -1;
// This is a trick. We double the stack slots so we can claim
// the oops in the caller's frame. Since we are sure to have
// more args than the caller doubling is enough to make
// sure we can capture all the incoming oop args from the
// caller.
//
OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
// Mark location of rfp (someday)
// map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, vmreg(rfp));
int float_args = 0;
int int_args = 0;
#ifdef ASSERT
bool reg_destroyed[RegisterImpl::number_of_registers];
bool freg_destroyed[FloatRegisterImpl::number_of_registers];
for ( int r = 0 ; r < RegisterImpl::number_of_registers ; r++ ) {
reg_destroyed[r] = false;
}
for ( int f = 0 ; f < FloatRegisterImpl::number_of_registers ; f++ ) {
freg_destroyed[f] = false;
}
#endif /* ASSERT */
// This may iterate in two different directions depending on the
// kind of native it is. The reason is that for regular JNI natives
// the incoming and outgoing registers are offset upwards and for
// critical natives they are offset down.
GrowableArray<int> arg_order(2 * total_in_args);
VMRegPair tmp_vmreg;
tmp_vmreg.set2(r19->as_VMReg());
if (!is_critical_native) {
for (int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0; i--, c_arg--) {
arg_order.push(i);
arg_order.push(c_arg);
}
} else {
// Compute a valid move order, using tmp_vmreg to break any cycles
ComputeMoveOrder cmo(total_in_args, in_regs, total_c_args, out_regs, in_sig_bt, arg_order, tmp_vmreg);
}
int temploc = -1;
for (int ai = 0; ai < arg_order.length(); ai += 2) {
int i = arg_order.at(ai);
int c_arg = arg_order.at(ai + 1);
__ block_comment(err_msg("move %d -> %d", i, c_arg));
if (c_arg == -1) {
assert(is_critical_native, "should only be required for critical natives");
// This arg needs to be moved to a temporary
__ mov(tmp_vmreg.first()->as_Register(), in_regs[i].first()->as_Register());
in_regs[i] = tmp_vmreg;
temploc = i;
continue;
} else if (i == -1) {
assert(is_critical_native, "should only be required for critical natives");
// Read from the temporary location
assert(temploc != -1, "must be valid");
i = temploc;
temploc = -1;
}
#ifdef ASSERT
if (in_regs[i].first()->is_Register()) {
assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "destroyed reg!");
} else if (in_regs[i].first()->is_FloatRegister()) {
assert(!freg_destroyed[in_regs[i].first()->as_FloatRegister()->encoding()], "destroyed reg!");
}
if (out_regs[c_arg].first()->is_Register()) {
reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
} else if (out_regs[c_arg].first()->is_FloatRegister()) {
freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
}
#endif /* ASSERT */
switch (in_sig_bt[i]) {
case T_ARRAY:
if (is_critical_native) {
unpack_array_argument(masm, in_regs[i], in_elem_bt[i], out_regs[c_arg + 1], out_regs[c_arg]);
c_arg++;
#ifdef ASSERT
if (out_regs[c_arg].first()->is_Register()) {
reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
} else if (out_regs[c_arg].first()->is_FloatRegister()) {
freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
}
#endif
int_args++;
break;
}
case T_OBJECT:
assert(!is_critical_native, "no oop arguments");
object_move(masm, map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],
((i == 0) && (!is_static)),
&receiver_offset);
int_args++;
break;
case T_VOID:
break;
case T_FLOAT:
float_move(masm, in_regs[i], out_regs[c_arg]);
float_args++;
break;
case T_DOUBLE:
assert( i + 1 < total_in_args &&
in_sig_bt[i + 1] == T_VOID &&
out_sig_bt[c_arg+1] == T_VOID, "bad arg list");
double_move(masm, in_regs[i], out_regs[c_arg]);
float_args++;
break;
case T_LONG :
long_move(masm, in_regs[i], out_regs[c_arg]);
int_args++;
break;
case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
default:
move32_64(masm, in_regs[i], out_regs[c_arg]);
int_args++;
}
}
// point c_arg at the first arg that is already loaded in case we
// need to spill before we call out
int c_arg = total_c_args - total_in_args;
// Pre-load a static method's oop into c_rarg1.
if (method->is_static() && !is_critical_native) {
// load oop into a register
__ movoop(c_rarg1,
JNIHandles::make_local(method->method_holder()->java_mirror()),
/*immediate*/true);
// Now handlize the static class mirror it's known not-null.
__ str(c_rarg1, Address(sp, klass_offset));
map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
// Now get the handle
__ lea(c_rarg1, Address(sp, klass_offset));
// and protect the arg if we must spill
c_arg--;
}
// Change state to native (we save the return address in the thread, since it might not
// be pushed on the stack when we do a stack traversal).
// We use the same pc/oopMap repeatedly when we call out
Label native_return;
__ set_last_Java_frame(sp, noreg, native_return, rscratch1);
Label dtrace_method_entry, dtrace_method_entry_done;
{
uint64_t offset;
__ adrp(rscratch1, ExternalAddress((address)&DTraceMethodProbes), offset);
__ ldrb(rscratch1, Address(rscratch1, offset));
__ cbnzw(rscratch1, dtrace_method_entry);
__ bind(dtrace_method_entry_done);
}
// RedefineClasses() tracing support for obsolete method entry
if (log_is_enabled(Trace, redefine, class, obsolete)) {
// protect the args we've loaded
save_args(masm, total_c_args, c_arg, out_regs);
__ mov_metadata(c_rarg1, method());
__ call_VM_leaf(
CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),
rthread, c_rarg1);
restore_args(masm, total_c_args, c_arg, out_regs);
}
// Lock a synchronized method
// Register definitions used by locking and unlocking
const Register swap_reg = r0;
const Register obj_reg = r19; // Will contain the oop
const Register lock_reg = r13; // Address of compiler lock object (BasicLock)
const Register old_hdr = r13; // value of old header at unlock time
const Register tmp = lr;
Label slow_path_lock;
Label lock_done;
if (method->is_synchronized()) {
assert(!is_critical_native, "unhandled");
const int mark_word_offset = BasicLock::displaced_header_offset_in_bytes();
// Get the handle (the 2nd argument)
__ mov(oop_handle_reg, c_rarg1);
// Get address of the box
__ lea(lock_reg, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
// Load the oop from the handle
__ ldr(obj_reg, Address(oop_handle_reg, 0));
if (UseBiasedLocking) {
__ biased_locking_enter(lock_reg, obj_reg, swap_reg, tmp, false, lock_done, &slow_path_lock);
}
// Load (object->mark() | 1) into swap_reg %r0
__ ldr(rscratch1, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
__ orr(swap_reg, rscratch1, 1);
// Save (object->mark() | 1) into BasicLock's displaced header
__ str(swap_reg, Address(lock_reg, mark_word_offset));
// src -> dest iff dest == r0 else r0 <- dest
{ Label here;
__ cmpxchg_obj_header(r0, lock_reg, obj_reg, rscratch1, lock_done, /*fallthrough*/NULL);
}
// Hmm should this move to the slow path code area???
// Test if the oopMark is an obvious stack pointer, i.e.,
// 1) (mark & 3) == 0, and
// 2) sp <= mark < mark + os::pagesize()
// These 3 tests can be done by evaluating the following
// expression: ((mark - sp) & (3 - os::vm_page_size())),
// assuming both stack pointer and pagesize have their
// least significant 2 bits clear.
// NOTE: the oopMark is in swap_reg %r0 as the result of cmpxchg
__ sub(swap_reg, sp, swap_reg);
__ neg(swap_reg, swap_reg);
__ ands(swap_reg, swap_reg, 3 - os::vm_page_size());
// Save the test result, for recursive case, the result is zero
__ str(swap_reg, Address(lock_reg, mark_word_offset));
__ br(Assembler::NE, slow_path_lock);
// Slow path will re-enter here
__ bind(lock_done);
}
// Finally just about ready to make the JNI call
// get JNIEnv* which is first argument to native
if (!is_critical_native) {
__ lea(c_rarg0, Address(rthread, in_bytes(JavaThread::jni_environment_offset())));
}
// Now set thread in native
__ mov(rscratch1, _thread_in_native);
__ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
__ stlrw(rscratch1, rscratch2);
rt_call(masm, native_func);
__ bind(native_return);
intptr_t return_pc = (intptr_t) __ pc();
oop_maps->add_gc_map(return_pc - start, map);
// Unpack native results.
switch (ret_type) {
case T_BOOLEAN: __ c2bool(r0); break;
case T_CHAR : __ ubfx(r0, r0, 0, 16); break;
case T_BYTE : __ sbfx(r0, r0, 0, 8); break;
case T_SHORT : __ sbfx(r0, r0, 0, 16); break;
case T_INT : __ sbfx(r0, r0, 0, 32); break;
case T_DOUBLE :
case T_FLOAT :
// Result is in v0 we'll save as needed
break;
case T_ARRAY: // Really a handle
case T_OBJECT: // Really a handle
break; // can't de-handlize until after safepoint check
case T_VOID: break;
case T_LONG: break;
default : ShouldNotReachHere();
}
// Switch thread to "native transition" state before reading the synchronization state.
// This additional state is necessary because reading and testing the synchronization
// state is not atomic w.r.t. GC, as this scenario demonstrates:
// Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.
// VM thread changes sync state to synchronizing and suspends threads for GC.
// Thread A is resumed to finish this native method, but doesn't block here since it
// didn't see any synchronization is progress, and escapes.
__ mov(rscratch1, _thread_in_native_trans);
if(os::is_MP()) {
if (UseMembar) {
__ strw(rscratch1, Address(rthread, JavaThread::thread_state_offset()));
// Force this write out before the read below
__ dmb(Assembler::ISH);
} else {
__ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
__ stlrw(rscratch1, rscratch2);
// Write serialization page so VM thread can do a pseudo remote membar.
// We use the current thread pointer to calculate a thread specific
// offset to write to within the page. This minimizes bus traffic
// due to cache line collision.
__ serialize_memory(rthread, r2);
}
} else {
__ strw(rscratch1, Address(rthread, JavaThread::thread_state_offset()));
}
// check for safepoint operation in progress and/or pending suspend requests
Label safepoint_in_progress, safepoint_in_progress_done;
{
__ safepoint_poll_acquire(safepoint_in_progress);
__ ldrw(rscratch1, Address(rthread, JavaThread::suspend_flags_offset()));
__ cbnzw(rscratch1, safepoint_in_progress);
__ bind(safepoint_in_progress_done);
}
// change thread state
Label after_transition;
__ mov(rscratch1, _thread_in_Java);
__ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
__ stlrw(rscratch1, rscratch2);
__ bind(after_transition);
Label reguard;
Label reguard_done;
__ ldrb(rscratch1, Address(rthread, JavaThread::stack_guard_state_offset()));
__ cmpw(rscratch1, JavaThread::stack_guard_yellow_reserved_disabled);
__ br(Assembler::EQ, reguard);
__ bind(reguard_done);
// native result if any is live
// Unlock
Label unlock_done;
Label slow_path_unlock;
if (method->is_synchronized()) {
// Get locked oop from the handle we passed to jni
__ ldr(obj_reg, Address(oop_handle_reg, 0));
Label done;
if (UseBiasedLocking) {
__ biased_locking_exit(obj_reg, old_hdr, done);
}
// Simple recursive lock?
__ ldr(rscratch1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
__ cbz(rscratch1, done);
// Must save r0 if if it is live now because cmpxchg must use it
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
save_native_result(masm, ret_type, stack_slots);
}
// get address of the stack lock
__ lea(r0, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
// get old displaced header
__ ldr(old_hdr, Address(r0, 0));
// Atomic swap old header if oop still contains the stack lock
Label succeed;
__ cmpxchg_obj_header(r0, old_hdr, obj_reg, rscratch1, succeed, &slow_path_unlock);
__ bind(succeed);
// slow path re-enters here
__ bind(unlock_done);
if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
restore_native_result(masm, ret_type, stack_slots);
}
__ bind(done);
}
Label dtrace_method_exit, dtrace_method_exit_done;
{
uint64_t offset;
__ adrp(rscratch1, ExternalAddress((address)&DTraceMethodProbes), offset);
__ ldrb(rscratch1, Address(rscratch1, offset));
__ cbnzw(rscratch1, dtrace_method_exit);
__ bind(dtrace_method_exit_done);
}
__ reset_last_Java_frame(false);
// Unbox oop result, e.g. JNIHandles::resolve result.
if (ret_type == T_OBJECT || ret_type == T_ARRAY) {
__ resolve_jobject(r0, rthread, rscratch2);
}
if (CheckJNICalls) {
// clear_pending_jni_exception_check
__ str(zr, Address(rthread, JavaThread::pending_jni_exception_check_fn_offset()));
}
if (!is_critical_native) {
// reset handle block
__ ldr(r2, Address(rthread, JavaThread::active_handles_offset()));
__ str(zr, Address(r2, JNIHandleBlock::top_offset_in_bytes()));
}
__ leave();
if (!is_critical_native) {
// Any exception pending?
__ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
__ cbnz(rscratch1, exception_pending);
}
// We're done
__ ret(lr);
// Unexpected paths are out of line and go here
if (!is_critical_native) {
// forward the exception
__ bind(exception_pending);
// and forward the exception
__ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
}
// Slow path locking & unlocking
if (method->is_synchronized()) {
__ block_comment("Slow path lock {");
__ bind(slow_path_lock);
// has last_Java_frame setup. No exceptions so do vanilla call not call_VM
// args are (oop obj, BasicLock* lock, JavaThread* thread)
// protect the args we've loaded
save_args(masm, total_c_args, c_arg, out_regs);
__ mov(c_rarg0, obj_reg);
__ mov(c_rarg1, lock_reg);
__ mov(c_rarg2, rthread);
// Not a leaf but we have last_Java_frame setup as we want
__ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), 3);
restore_args(masm, total_c_args, c_arg, out_regs);
#ifdef ASSERT
{ Label L;
__ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
__ cbz(rscratch1, L);
__ stop("no pending exception allowed on exit from monitorenter");
__ bind(L);
}
#endif
__ b(lock_done);
__ block_comment("} Slow path lock");
__ block_comment("Slow path unlock {");
__ bind(slow_path_unlock);
// If we haven't already saved the native result we must save it now as xmm registers
// are still exposed.
if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
save_native_result(masm, ret_type, stack_slots);
}
__ mov(c_rarg2, rthread);
__ lea(c_rarg1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
__ mov(c_rarg0, obj_reg);
// Save pending exception around call to VM (which contains an EXCEPTION_MARK)
// NOTE that obj_reg == r19 currently
__ ldr(r19, Address(rthread, in_bytes(Thread::pending_exception_offset())));
__ str(zr, Address(rthread, in_bytes(Thread::pending_exception_offset())));
rt_call(masm, CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C));
#ifdef ASSERT
{
Label L;
__ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
__ cbz(rscratch1, L);
__ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
__ bind(L);
}
#endif /* ASSERT */
__ str(r19, Address(rthread, in_bytes(Thread::pending_exception_offset())));
if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
restore_native_result(masm, ret_type, stack_slots);
}
__ b(unlock_done);
__ block_comment("} Slow path unlock");
} // synchronized
// SLOW PATH Reguard the stack if needed
__ bind(reguard);
save_native_result(masm, ret_type, stack_slots);
rt_call(masm, CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages));
restore_native_result(masm, ret_type, stack_slots);
// and continue
__ b(reguard_done);
// SLOW PATH safepoint
{
__ block_comment("safepoint {");
__ bind(safepoint_in_progress);
// Don't use call_VM as it will see a possible pending exception and forward it
// and never return here preventing us from clearing _last_native_pc down below.
//
save_native_result(masm, ret_type, stack_slots);
__ mov(c_rarg0, rthread);
#ifndef PRODUCT
assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
#endif
if (!is_critical_native) {
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans)));
} else {
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans_and_transition)));
}
__ blr(rscratch1);
__ maybe_isb();
// Restore any method result value
restore_native_result(masm, ret_type, stack_slots);
if (is_critical_native) {
// The call above performed the transition to thread_in_Java so
// skip the transition logic above.
__ b(after_transition);
}
__ b(safepoint_in_progress_done);
__ block_comment("} safepoint");
}
// SLOW PATH dtrace support
{
__ block_comment("dtrace entry {");
__ bind(dtrace_method_entry);
// We have all of the arguments setup at this point. We must not touch any register
// argument registers at this point (what if we save/restore them there are no oop?
save_args(masm, total_c_args, c_arg, out_regs);
__ mov_metadata(c_rarg1, method());
__ call_VM_leaf(
CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
rthread, c_rarg1);
restore_args(masm, total_c_args, c_arg, out_regs);
__ b(dtrace_method_entry_done);
__ block_comment("} dtrace entry");
}
{
__ block_comment("dtrace exit {");
__ bind(dtrace_method_exit);
save_native_result(masm, ret_type, stack_slots);
__ mov_metadata(c_rarg1, method());
__ call_VM_leaf(
CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
rthread, c_rarg1);
restore_native_result(masm, ret_type, stack_slots);
__ b(dtrace_method_exit_done);
__ block_comment("} dtrace exit");
}
__ flush();
nmethod *nm = nmethod::new_native_nmethod(method,
compile_id,
masm->code(),
vep_offset,
frame_complete,
stack_slots / VMRegImpl::slots_per_word,
(is_static ? in_ByteSize(klass_offset) : in_ByteSize(receiver_offset)),
in_ByteSize(lock_slot_offset*VMRegImpl::stack_slot_size),
oop_maps);
if (is_critical_native) {
nm->set_lazy_critical_native(true);
}
return nm;
}
// this function returns the adjust size (in number of words) to a c2i adapter
// activation for use during deoptimization
int Deoptimization::last_frame_adjust(int callee_parameters, int callee_locals) {
assert(callee_locals >= callee_parameters,
"test and remove; got more parms than locals");
if (callee_locals < callee_parameters)
return 0; // No adjustment for negative locals
int diff = (callee_locals - callee_parameters) * Interpreter::stackElementWords;
// diff is counted in stack words
return align_up(diff, 2);
}
//------------------------------generate_deopt_blob----------------------------
void SharedRuntime::generate_deopt_blob() {
// Allocate space for the code
ResourceMark rm;
// Setup code generation tools
int pad = 0;
#if INCLUDE_JVMCI
if (EnableJVMCI || UseAOT) {
pad += 512; // Increase the buffer size when compiling for JVMCI
}
#endif
CodeBuffer buffer("deopt_blob", 2048+pad, 1024);
MacroAssembler* masm = new MacroAssembler(&buffer);
int frame_size_in_words;
OopMap* map = NULL;
OopMapSet *oop_maps = new OopMapSet();
// -------------
// This code enters when returning to a de-optimized nmethod. A return
// address has been pushed on the the stack, and return values are in
// registers.
// If we are doing a normal deopt then we were called from the patched
// nmethod from the point we returned to the nmethod. So the return
// address on the stack is wrong by NativeCall::instruction_size
// We will adjust the value so it looks like we have the original return
// address on the stack (like when we eagerly deoptimized).
// In the case of an exception pending when deoptimizing, we enter
// with a return address on the stack that points after the call we patched
// into the exception handler. We have the following register state from,
// e.g., the forward exception stub (see stubGenerator_x86_64.cpp).
// r0: exception oop
// r19: exception handler
// r3: throwing pc
// So in this case we simply jam r3 into the useless return address and
// the stack looks just like we want.
//
// At this point we need to de-opt. We save the argument return
// registers. We call the first C routine, fetch_unroll_info(). This
// routine captures the return values and returns a structure which
// describes the current frame size and the sizes of all replacement frames.
// The current frame is compiled code and may contain many inlined
// functions, each with their own JVM state. We pop the current frame, then
// push all the new frames. Then we call the C routine unpack_frames() to
// populate these frames. Finally unpack_frames() returns us the new target
// address. Notice that callee-save registers are BLOWN here; they have
// already been captured in the vframeArray at the time the return PC was
// patched.
address start = __ pc();
Label cont;
// Prolog for non exception case!
// Save everything in sight.
map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
// Normal deoptimization. Save exec mode for unpack_frames.
__ movw(rcpool, Deoptimization::Unpack_deopt); // callee-saved
__ b(cont);
int reexecute_offset = __ pc() - start;
#if INCLUDE_JVMCI && !defined(COMPILER1)
if (EnableJVMCI && UseJVMCICompiler) {
// JVMCI does not use this kind of deoptimization
__ should_not_reach_here();
}
#endif
// Reexecute case
// return address is the pc describes what bci to do re-execute at
// No need to update map as each call to save_live_registers will produce identical oopmap
(void) RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
__ movw(rcpool, Deoptimization::Unpack_reexecute); // callee-saved
__ b(cont);
#if INCLUDE_JVMCI
Label after_fetch_unroll_info_call;
int implicit_exception_uncommon_trap_offset = 0;
int uncommon_trap_offset = 0;
if (EnableJVMCI || UseAOT) {
implicit_exception_uncommon_trap_offset = __ pc() - start;
__ ldr(lr, Address(rthread, in_bytes(JavaThread::jvmci_implicit_exception_pc_offset())));
__ str(zr, Address(rthread, in_bytes(JavaThread::jvmci_implicit_exception_pc_offset())));
uncommon_trap_offset = __ pc() - start;
// Save everything in sight.
RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
// fetch_unroll_info needs to call last_java_frame()
Label retaddr;
__ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
__ ldrw(c_rarg1, Address(rthread, in_bytes(JavaThread::pending_deoptimization_offset())));
__ movw(rscratch1, -1);
__ strw(rscratch1, Address(rthread, in_bytes(JavaThread::pending_deoptimization_offset())));
__ movw(rcpool, (int32_t)Deoptimization::Unpack_reexecute);
__ mov(c_rarg0, rthread);
__ movw(c_rarg2, rcpool); // exec mode
__ lea(rscratch1,
RuntimeAddress(CAST_FROM_FN_PTR(address,
Deoptimization::uncommon_trap)));
__ blr(rscratch1);
__ bind(retaddr);
oop_maps->add_gc_map( __ pc()-start, map->deep_copy());
__ reset_last_Java_frame(false);
__ b(after_fetch_unroll_info_call);
} // EnableJVMCI
#endif // INCLUDE_JVMCI
int exception_offset = __ pc() - start;
// Prolog for exception case
// all registers are dead at this entry point, except for r0, and
// r3 which contain the exception oop and exception pc
// respectively. Set them in TLS and fall thru to the
// unpack_with_exception_in_tls entry point.
__ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
__ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
int exception_in_tls_offset = __ pc() - start;
// new implementation because exception oop is now passed in JavaThread
// Prolog for exception case
// All registers must be preserved because they might be used by LinearScan
// Exceptiop oop and throwing PC are passed in JavaThread
// tos: stack at point of call to method that threw the exception (i.e. only
// args are on the stack, no return address)
// The return address pushed by save_live_registers will be patched
// later with the throwing pc. The correct value is not available
// now because loading it from memory would destroy registers.
// NB: The SP at this point must be the SP of the method that is
// being deoptimized. Deoptimization assumes that the frame created
// here by save_live_registers is immediately below the method's SP.
// This is a somewhat fragile mechanism.
// Save everything in sight.
map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
// Now it is safe to overwrite any register
// Deopt during an exception. Save exec mode for unpack_frames.
__ mov(rcpool, Deoptimization::Unpack_exception); // callee-saved
// load throwing pc from JavaThread and patch it as the return address
// of the current frame. Then clear the field in JavaThread
__ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
__ str(r3, Address(rfp, wordSize));
__ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
#ifdef ASSERT
// verify that there is really an exception oop in JavaThread
__ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
__ verify_oop(r0);
// verify that there is no pending exception
Label no_pending_exception;
__ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
__ cbz(rscratch1, no_pending_exception);
__ stop("must not have pending exception here");
__ bind(no_pending_exception);
#endif
__ bind(cont);
// Call C code. Need thread and this frame, but NOT official VM entry
// crud. We cannot block on this call, no GC can happen.
//
// UnrollBlock* fetch_unroll_info(JavaThread* thread)
// fetch_unroll_info needs to call last_java_frame().
Label retaddr;
__ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
#ifdef ASSERT0
{ Label L;
__ ldr(rscratch1, Address(rthread,
JavaThread::last_Java_fp_offset()));
__ cbz(rscratch1, L);
__ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
__ bind(L);
}
#endif // ASSERT
__ mov(c_rarg0, rthread);
__ mov(c_rarg1, rcpool);
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::fetch_unroll_info)));
__ blr(rscratch1);
__ bind(retaddr);
// Need to have an oopmap that tells fetch_unroll_info where to
// find any register it might need.
oop_maps->add_gc_map(__ pc() - start, map);
__ reset_last_Java_frame(false);
#if INCLUDE_JVMCI
if (EnableJVMCI || UseAOT) {
__ bind(after_fetch_unroll_info_call);
}
#endif
// Load UnrollBlock* into r5
__ mov(r5, r0);
__ ldrw(rcpool, Address(r5, Deoptimization::UnrollBlock::unpack_kind_offset_in_bytes()));
Label noException;
__ cmpw(rcpool, Deoptimization::Unpack_exception); // Was exception pending?
__ br(Assembler::NE, noException);
__ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
// QQQ this is useless it was NULL above
__ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
__ str(zr, Address(rthread, JavaThread::exception_oop_offset()));
__ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
__ verify_oop(r0);
// Overwrite the result registers with the exception results.
__ str(r0, Address(sp, RegisterSaver::r0_offset_in_bytes()));
// I think this is useless
// __ str(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
__ bind(noException);
// Only register save data is on the stack.
// Now restore the result registers. Everything else is either dead
// or captured in the vframeArray.
RegisterSaver::restore_result_registers(masm);
// All of the register save area has been popped of the stack. Only the
// return address remains.
// Pop all the frames we must move/replace.
//
// Frame picture (youngest to oldest)
// 1: self-frame (no frame link)
// 2: deopting frame (no frame link)
// 3: caller of deopting frame (could be compiled/interpreted).
//
// Note: by leaving the return address of self-frame on the stack
// and using the size of frame 2 to adjust the stack
// when we are done the return to frame 3 will still be on the stack.
// Pop deoptimized frame
__ ldrw(r2, Address(r5, Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset_in_bytes()));
__ sub(r2, r2, 2 * wordSize);
__ add(sp, sp, r2);
__ ldp(rfp, lr, __ post(sp, 2 * wordSize));
// LR should now be the return address to the caller (3)
#ifdef ASSERT
// Compilers generate code that bang the stack by as much as the
// interpreter would need. So this stack banging should never
// trigger a fault. Verify that it does not on non product builds.
if (UseStackBanging) {
__ ldrw(r19, Address(r5, Deoptimization::UnrollBlock::total_frame_sizes_offset_in_bytes()));
__ bang_stack_size(r19, r2);
}
#endif
// Load address of array of frame pcs into r2
__ ldr(r2, Address(r5, Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
// Trash the old pc
// __ addptr(sp, wordSize); FIXME ????
// Load address of array of frame sizes into r4
__ ldr(r4, Address(r5, Deoptimization::UnrollBlock::frame_sizes_offset_in_bytes()));
// Load counter into r3
__ ldrw(r3, Address(r5, Deoptimization::UnrollBlock::number_of_frames_offset_in_bytes()));
// Now adjust the caller's stack to make up for the extra locals
// but record the original sp so that we can save it in the skeletal interpreter
// frame and the stack walking of interpreter_sender will get the unextended sp
// value and not the "real" sp value.
const Register sender_sp = r6;
__ mov(sender_sp, sp);
__ ldrw(r19, Address(r5,
Deoptimization::UnrollBlock::
caller_adjustment_offset_in_bytes()));
__ sub(sp, sp, r19);
// Push interpreter frames in a loop
__ mov(rscratch1, (address)0xDEADDEAD); // Make a recognizable pattern
__ mov(rscratch2, rscratch1);
Label loop;
__ bind(loop);
__ ldr(r19, Address(__ post(r4, wordSize))); // Load frame size
__ sub(r19, r19, 2*wordSize); // We'll push pc and fp by hand
__ ldr(lr, Address(__ post(r2, wordSize))); // Load pc
__ enter(); // Save old & set new fp
__ sub(sp, sp, r19); // Prolog
// This value is corrected by layout_activation_impl
__ str(zr, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize));
__ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
__ mov(sender_sp, sp); // Pass sender_sp to next frame
__ sub(r3, r3, 1); // Decrement counter
__ cbnz(r3, loop);
// Re-push self-frame
__ ldr(lr, Address(r2));
__ enter();
// Allocate a full sized register save area. We subtract 2 because
// enter() just pushed 2 words
__ sub(sp, sp, (frame_size_in_words - 2) * wordSize);
// Restore frame locals after moving the frame
__ strd(v0, Address(sp, RegisterSaver::v0_offset_in_bytes()));
__ str(r0, Address(sp, RegisterSaver::r0_offset_in_bytes()));
// Call C code. Need thread but NOT official VM entry
// crud. We cannot block on this call, no GC can happen. Call should
// restore return values to their stack-slots with the new SP.
//
// void Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)
// Use rfp because the frames look interpreted now
// Don't need the precise return PC here, just precise enough to point into this code blob.
address the_pc = __ pc();
__ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
__ mov(c_rarg0, rthread);
__ movw(c_rarg1, rcpool); // second arg: exec_mode
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
__ blr(rscratch1);
// Set an oopmap for the call site
// Use the same PC we used for the last java frame
oop_maps->add_gc_map(the_pc - start,
new OopMap( frame_size_in_words, 0 ));
// Clear fp AND pc
__ reset_last_Java_frame(true);
// Collect return values
__ ldrd(v0, Address(sp, RegisterSaver::v0_offset_in_bytes()));
__ ldr(r0, Address(sp, RegisterSaver::r0_offset_in_bytes()));
// I think this is useless (throwing pc?)
// __ ldr(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
// Pop self-frame.
__ leave(); // Epilog
// Jump to interpreter
__ ret(lr);
// Make sure all code is generated
masm->flush();
_deopt_blob = DeoptimizationBlob::create(&buffer, oop_maps, 0, exception_offset, reexecute_offset, frame_size_in_words);
_deopt_blob->set_unpack_with_exception_in_tls_offset(exception_in_tls_offset);
#if INCLUDE_JVMCI
if (EnableJVMCI || UseAOT) {
_deopt_blob->set_uncommon_trap_offset(uncommon_trap_offset);
_deopt_blob->set_implicit_exception_uncommon_trap_offset(implicit_exception_uncommon_trap_offset);
}
#endif
}
uint SharedRuntime::out_preserve_stack_slots() {
return 0;
}
#if COMPILER2_OR_JVMCI
//------------------------------generate_uncommon_trap_blob--------------------
void SharedRuntime::generate_uncommon_trap_blob() {
// Allocate space for the code
ResourceMark rm;
// Setup code generation tools
CodeBuffer buffer("uncommon_trap_blob", 2048, 1024);
MacroAssembler* masm = new MacroAssembler(&buffer);
assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
address start = __ pc();
// Push self-frame. We get here with a return address in LR
// and sp should be 16 byte aligned
// push rfp and retaddr by hand
__ stp(rfp, lr, Address(__ pre(sp, -2 * wordSize)));
// we don't expect an arg reg save area
#ifndef PRODUCT
assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
#endif
// compiler left unloaded_class_index in j_rarg0 move to where the
// runtime expects it.
if (c_rarg1 != j_rarg0) {
__ movw(c_rarg1, j_rarg0);
}
// we need to set the past SP to the stack pointer of the stub frame
// and the pc to the address where this runtime call will return
// although actually any pc in this code blob will do).
Label retaddr;
__ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
// Call C code. Need thread but NOT official VM entry
// crud. We cannot block on this call, no GC can happen. Call should
// capture callee-saved registers as well as return values.
// Thread is in rdi already.
//
// UnrollBlock* uncommon_trap(JavaThread* thread, jint unloaded_class_index);
//
// n.b. 2 gp args, 0 fp args, integral return type
__ mov(c_rarg0, rthread);
__ movw(c_rarg2, (unsigned)Deoptimization::Unpack_uncommon_trap);
__ lea(rscratch1,
RuntimeAddress(CAST_FROM_FN_PTR(address,
Deoptimization::uncommon_trap)));
__ blr(rscratch1);
__ bind(retaddr);
// Set an oopmap for the call site
OopMapSet* oop_maps = new OopMapSet();
OopMap* map = new OopMap(SimpleRuntimeFrame::framesize, 0);
// location of rfp is known implicitly by the frame sender code
oop_maps->add_gc_map(__ pc() - start, map);
__ reset_last_Java_frame(false);
// move UnrollBlock* into r4
__ mov(r4, r0);
#ifdef ASSERT
{ Label L;
__ ldrw(rscratch1, Address(r4, Deoptimization::UnrollBlock::unpack_kind_offset_in_bytes()));
__ cmpw(rscratch1, (unsigned)Deoptimization::Unpack_uncommon_trap);
__ br(Assembler::EQ, L);
__ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
__ bind(L);
}
#endif
// Pop all the frames we must move/replace.
//
// Frame picture (youngest to oldest)
// 1: self-frame (no frame link)
// 2: deopting frame (no frame link)
// 3: caller of deopting frame (could be compiled/interpreted).
// Pop self-frame. We have no frame, and must rely only on r0 and sp.
__ add(sp, sp, (SimpleRuntimeFrame::framesize) << LogBytesPerInt); // Epilog!
// Pop deoptimized frame (int)
__ ldrw(r2, Address(r4,
Deoptimization::UnrollBlock::
size_of_deoptimized_frame_offset_in_bytes()));
__ sub(r2, r2, 2 * wordSize);
__ add(sp, sp, r2);
__ ldp(rfp, lr, __ post(sp, 2 * wordSize));
// LR should now be the return address to the caller (3) frame
#ifdef ASSERT
// Compilers generate code that bang the stack by as much as the
// interpreter would need. So this stack banging should never
// trigger a fault. Verify that it does not on non product builds.
if (UseStackBanging) {
__ ldrw(r1, Address(r4,
Deoptimization::UnrollBlock::
total_frame_sizes_offset_in_bytes()));
__ bang_stack_size(r1, r2);
}
#endif
// Load address of array of frame pcs into r2 (address*)
__ ldr(r2, Address(r4,
Deoptimization::UnrollBlock::frame_pcs_offset_in_bytes()));
// Load address of array of frame sizes into r5 (intptr_t*)
__ ldr(r5, Address(r4,
Deoptimization::UnrollBlock::
frame_sizes_offset_in_bytes()));
// Counter
__ ldrw(r3, Address(r4,
Deoptimization::UnrollBlock::
number_of_frames_offset_in_bytes())); // (int)
// Now adjust the caller's stack to make up for the extra locals but
// record the original sp so that we can save it in the skeletal
// interpreter frame and the stack walking of interpreter_sender
// will get the unextended sp value and not the "real" sp value.
const Register sender_sp = r8;
__ mov(sender_sp, sp);
__ ldrw(r1, Address(r4,
Deoptimization::UnrollBlock::
caller_adjustment_offset_in_bytes())); // (int)
__ sub(sp, sp, r1);
// Push interpreter frames in a loop
Label loop;
__ bind(loop);
__ ldr(r1, Address(r5, 0)); // Load frame size
__ sub(r1, r1, 2 * wordSize); // We'll push pc and rfp by hand
__ ldr(lr, Address(r2, 0)); // Save return address
__ enter(); // and old rfp & set new rfp
__ sub(sp, sp, r1); // Prolog
__ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
// This value is corrected by layout_activation_impl
__ str(zr, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize));
__ mov(sender_sp, sp); // Pass sender_sp to next frame
__ add(r5, r5, wordSize); // Bump array pointer (sizes)
__ add(r2, r2, wordSize); // Bump array pointer (pcs)
__ subsw(r3, r3, 1); // Decrement counter
__ br(Assembler::GT, loop);
__ ldr(lr, Address(r2, 0)); // save final return address
// Re-push self-frame
__ enter(); // & old rfp & set new rfp
// Use rfp because the frames look interpreted now
// Save "the_pc" since it cannot easily be retrieved using the last_java_SP after we aligned SP.
// Don't need the precise return PC here, just precise enough to point into this code blob.
address the_pc = __ pc();
__ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
// Call C code. Need thread but NOT official VM entry
// crud. We cannot block on this call, no GC can happen. Call should
// restore return values to their stack-slots with the new SP.
// Thread is in rdi already.
//
// BasicType unpack_frames(JavaThread* thread, int exec_mode);
//
// n.b. 2 gp args, 0 fp args, integral return type
// sp should already be aligned
__ mov(c_rarg0, rthread);
__ movw(c_rarg1, (unsigned)Deoptimization::Unpack_uncommon_trap);
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
__ blr(rscratch1);
// Set an oopmap for the call site
// Use the same PC we used for the last java frame
oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
// Clear fp AND pc
__ reset_last_Java_frame(true);
// Pop self-frame.
__ leave(); // Epilog
// Jump to interpreter
__ ret(lr);
// Make sure all code is generated
masm->flush();
_uncommon_trap_blob = UncommonTrapBlob::create(&buffer, oop_maps,
SimpleRuntimeFrame::framesize >> 1);
}
#endif // COMPILER2_OR_JVMCI
//------------------------------generate_handler_blob------
//
// Generate a special Compile2Runtime blob that saves all registers,
// and setup oopmap.
//
SafepointBlob* SharedRuntime::generate_handler_blob(address call_ptr, int poll_type) {
ResourceMark rm;
OopMapSet *oop_maps = new OopMapSet();
OopMap* map;
// Allocate space for the code. Setup code generation tools.
CodeBuffer buffer("handler_blob", 2048, 1024);
MacroAssembler* masm = new MacroAssembler(&buffer);
address start = __ pc();
address call_pc = NULL;
int frame_size_in_words;
bool cause_return = (poll_type == POLL_AT_RETURN);
bool save_vectors = (poll_type == POLL_AT_VECTOR_LOOP);
// Save Integer and Float registers.
map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words, save_vectors);
// The following is basically a call_VM. However, we need the precise
// address of the call in order to generate an oopmap. Hence, we do all the
// work outselves.
Label retaddr;
__ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
// The return address must always be correct so that frame constructor never
// sees an invalid pc.
if (!cause_return) {
// overwrite the return address pushed by save_live_registers
// Additionally, r20 is a callee-saved register so we can look at
// it later to determine if someone changed the return address for
// us!
__ ldr(r20, Address(rthread, JavaThread::saved_exception_pc_offset()));
__ str(r20, Address(rfp, wordSize));
}
// Do the call
__ mov(c_rarg0, rthread);
__ lea(rscratch1, RuntimeAddress(call_ptr));
__ blr(rscratch1);
__ bind(retaddr);
// Set an oopmap for the call site. This oopmap will map all
// oop-registers and debug-info registers as callee-saved. This
// will allow deoptimization at this safepoint to find all possible
// debug-info recordings, as well as let GC find all oops.
oop_maps->add_gc_map( __ pc() - start, map);
Label noException;
__ reset_last_Java_frame(false);
__ maybe_isb();
__ membar(Assembler::LoadLoad | Assembler::LoadStore);
__ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
__ cbz(rscratch1, noException);
// Exception pending
RegisterSaver::restore_live_registers(masm, save_vectors);
__ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
// No exception case
__ bind(noException);
Label no_adjust, bail;
if (SafepointMechanism::uses_thread_local_poll() && !cause_return) {
// If our stashed return pc was modified by the runtime we avoid touching it
__ ldr(rscratch1, Address(rfp, wordSize));
__ cmp(r20, rscratch1);
__ br(Assembler::NE, no_adjust);
#ifdef ASSERT
// Verify the correct encoding of the poll we're about to skip.
// See NativeInstruction::is_ldrw_to_zr()
__ ldrw(rscratch1, Address(r20));
__ ubfx(rscratch2, rscratch1, 22, 10);
__ cmpw(rscratch2, 0b1011100101);
__ br(Assembler::NE, bail);
__ ubfx(rscratch2, rscratch1, 0, 5);
__ cmpw(rscratch2, 0b11111);
__ br(Assembler::NE, bail);
#endif
// Adjust return pc forward to step over the safepoint poll instruction
__ add(r20, r20, NativeInstruction::instruction_size);
__ str(r20, Address(rfp, wordSize));
}
__ bind(no_adjust);
// Normal exit, restore registers and exit.
RegisterSaver::restore_live_registers(masm, save_vectors);
__ ret(lr);
#ifdef ASSERT
__ bind(bail);
__ stop("Attempting to adjust pc to skip safepoint poll but the return point is not what we expected");
#endif
// Make sure all code is generated
masm->flush();
// Fill-out other meta info
return SafepointBlob::create(&buffer, oop_maps, frame_size_in_words);
}
//
// generate_resolve_blob - call resolution (static/virtual/opt-virtual/ic-miss
//
// Generate a stub that calls into vm to find out the proper destination
// of a java call. All the argument registers are live at this point
// but since this is generic code we don't know what they are and the caller
// must do any gc of the args.
//
RuntimeStub* SharedRuntime::generate_resolve_blob(address destination, const char* name) {
assert (StubRoutines::forward_exception_entry() != NULL, "must be generated before");
// allocate space for the code
ResourceMark rm;
CodeBuffer buffer(name, 1000, 512);
MacroAssembler* masm = new MacroAssembler(&buffer);
int frame_size_in_words;
OopMapSet *oop_maps = new OopMapSet();
OopMap* map = NULL;
int start = __ offset();
map = RegisterSaver::save_live_registers(masm, 0, &frame_size_in_words);
int frame_complete = __ offset();
{
Label retaddr;
__ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
__ mov(c_rarg0, rthread);
__ lea(rscratch1, RuntimeAddress(destination));
__ blr(rscratch1);
__ bind(retaddr);
}
// Set an oopmap for the call site.
// We need this not only for callee-saved registers, but also for volatile
// registers that the compiler might be keeping live across a safepoint.
oop_maps->add_gc_map( __ offset() - start, map);
__ maybe_isb();
// r0 contains the address we are going to jump to assuming no exception got installed
// clear last_Java_sp
__ reset_last_Java_frame(false);
// check for pending exceptions
Label pending;
__ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
__ cbnz(rscratch1, pending);
// get the returned Method*
__ get_vm_result_2(rmethod, rthread);
__ str(rmethod, Address(sp, RegisterSaver::reg_offset_in_bytes(rmethod)));
// r0 is where we want to jump, overwrite rscratch1 which is saved and scratch
__ str(r0, Address(sp, RegisterSaver::rscratch1_offset_in_bytes()));
RegisterSaver::restore_live_registers(masm);
// We are back the the original state on entry and ready to go.
__ br(rscratch1);
// Pending exception after the safepoint
__ bind(pending);
RegisterSaver::restore_live_registers(masm);
// exception pending => remove activation and forward to exception handler
__ str(zr, Address(rthread, JavaThread::vm_result_offset()));
__ ldr(r0, Address(rthread, Thread::pending_exception_offset()));
__ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
// -------------
// make sure all code is generated
masm->flush();
// return the blob
// frame_size_words or bytes??
return RuntimeStub::new_runtime_stub(name, &buffer, frame_complete, frame_size_in_words, oop_maps, true);
}
#if COMPILER2_OR_JVMCI
// This is here instead of runtime_x86_64.cpp because it uses SimpleRuntimeFrame
//
//------------------------------generate_exception_blob---------------------------
// creates exception blob at the end
// Using exception blob, this code is jumped from a compiled method.
// (see emit_exception_handler in x86_64.ad file)
//
// Given an exception pc at a call we call into the runtime for the
// handler in this method. This handler might merely restore state
// (i.e. callee save registers) unwind the frame and jump to the
// exception handler for the nmethod if there is no Java level handler
// for the nmethod.
//
// This code is entered with a jmp.
//
// Arguments:
// r0: exception oop
// r3: exception pc
//
// Results:
// r0: exception oop
// r3: exception pc in caller or ???
// destination: exception handler of caller
//
// Note: the exception pc MUST be at a call (precise debug information)
// Registers r0, r3, r2, r4, r5, r8-r11 are not callee saved.
//
void OptoRuntime::generate_exception_blob() {
assert(!OptoRuntime::is_callee_saved_register(R3_num), "");
assert(!OptoRuntime::is_callee_saved_register(R0_num), "");
assert(!OptoRuntime::is_callee_saved_register(R2_num), "");
assert(SimpleRuntimeFrame::framesize % 4 == 0, "sp not 16-byte aligned");
// Allocate space for the code
ResourceMark rm;
// Setup code generation tools
CodeBuffer buffer("exception_blob", 2048, 1024);
MacroAssembler* masm = new MacroAssembler(&buffer);
// TODO check various assumptions made here
//
// make sure we do so before running this
address start = __ pc();
// push rfp and retaddr by hand
// Exception pc is 'return address' for stack walker
__ stp(rfp, lr, Address(__ pre(sp, -2 * wordSize)));
// there are no callee save registers and we don't expect an
// arg reg save area
#ifndef PRODUCT
assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
#endif
// Store exception in Thread object. We cannot pass any arguments to the
// handle_exception call, since we do not want to make any assumption
// about the size of the frame where the exception happened in.
__ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
__ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
// This call does all the hard work. It checks if an exception handler
// exists in the method.
// If so, it returns the handler address.
// If not, it prepares for stack-unwinding, restoring the callee-save
// registers of the frame being removed.
//
// address OptoRuntime::handle_exception_C(JavaThread* thread)
//
// n.b. 1 gp arg, 0 fp args, integral return type
// the stack should always be aligned
address the_pc = __ pc();
__ set_last_Java_frame(sp, noreg, the_pc, rscratch1);
__ mov(c_rarg0, rthread);
__ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
__ blr(rscratch1);
__ maybe_isb();
// Set an oopmap for the call site. This oopmap will only be used if we
// are unwinding the stack. Hence, all locations will be dead.
// Callee-saved registers will be the same as the frame above (i.e.,
// handle_exception_stub), since they were restored when we got the
// exception.
OopMapSet* oop_maps = new OopMapSet();
oop_maps->add_gc_map(the_pc - start, new OopMap(SimpleRuntimeFrame::framesize, 0));
__ reset_last_Java_frame(false);
// Restore callee-saved registers
// rfp is an implicitly saved callee saved register (i.e. the calling
// convention will save restore it in prolog/epilog) Other than that
// there are no callee save registers now that adapter frames are gone.
// and we dont' expect an arg reg save area
__ ldp(rfp, r3, Address(__ post(sp, 2 * wordSize)));
// r0: exception handler
// We have a handler in r0 (could be deopt blob).
__ mov(r8, r0);
// Get the exception oop
__ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
// Get the exception pc in case we are deoptimized
__ ldr(r4, Address(rthread, JavaThread::exception_pc_offset()));
#ifdef ASSERT
__ str(zr, Address(rthread, JavaThread::exception_handler_pc_offset()));
__ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
#endif
// Clear the exception oop so GC no longer processes it as a root.
__ str(zr, Address(rthread, JavaThread::exception_oop_offset()));
// r0: exception oop
// r8: exception handler
// r4: exception pc
// Jump to handler
__ br(r8);
// Make sure all code is generated
masm->flush();
// Set exception blob
_exception_blob = ExceptionBlob::create(&buffer, oop_maps, SimpleRuntimeFrame::framesize >> 1);
}
#endif // COMPILER2_OR_JVMCI