| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include <platform/bionic/tls_defines.h> |
| #include <private/bionic_asm.h> |
| |
| .globl __tls_get_addr |
| |
| // These resolver functions must preserve every register except x0. They set x0 |
| // to the offset of the TLS symbol relative to the thread pointer. |
| |
| ENTRY_PRIVATE(tlsdesc_resolver_static) |
| ldr x0, [x0, #8] |
| ret |
| END(tlsdesc_resolver_static) |
| |
| ENTRY_PRIVATE(tlsdesc_resolver_dynamic) |
| stp x19, x20, [sp, #-32]! |
| .cfi_def_cfa_offset 32 |
| .cfi_rel_offset x19, 0 |
| .cfi_rel_offset x20, 8 |
| stp x21, x22, [sp, #16] |
| .cfi_rel_offset x21, 16 |
| .cfi_rel_offset x22, 24 |
| |
| mrs x19, tpidr_el0 // __get_tls() |
| ldr x20, [x19, #(TLS_SLOT_DTV * 8)] |
| ldr x21, [x20] // TlsDtv::generation |
| |
| ldr x0, [x0, #8] // TlsDynamicResolverArg* |
| ldr x22, [x0] // TlsDynamicResolverArg::generation |
| |
| cmp x21, x22 |
| b.lo .fallback |
| |
| ldr x21, [x0, #8] // TlsIndex::module |
| ldr x22, [x0, #16] // TlsIndex::offset |
| ldr x21, [x20, x21, lsl #3] // TlsDtv::modules[module] |
| cbz x21, .fallback |
| add x0, x21, x22 |
| sub x0, x0, x19 |
| |
| ldp x21, x22, [sp, #16] |
| .cfi_remember_state |
| .cfi_restore x21 |
| .cfi_restore x22 |
| ldp x19, x20, [sp], #32 |
| .cfi_adjust_cfa_offset -32 |
| .cfi_restore x19 |
| .cfi_restore x20 |
| ret |
| |
| .fallback: |
| .cfi_restore_state |
| ldp x21, x22, [sp, #16] |
| .cfi_restore x21 |
| .cfi_restore x22 |
| ldp x19, x20, [sp], #32 |
| .cfi_adjust_cfa_offset -32 |
| .cfi_restore x19 |
| .cfi_restore x20 |
| b tlsdesc_resolver_dynamic_slow_path |
| END(tlsdesc_resolver_dynamic) |
| |
| #define SAVE_REG(x, slot) \ |
| str x, [sp, #((slot) * 8)]; \ |
| .cfi_rel_offset x, (slot) * 8; \ |
| |
| #define SAVE_GPR_PAIR(x, y, slot) \ |
| stp x, y, [sp, #((slot) * 8)]; \ |
| .cfi_rel_offset x, (slot) * 8; \ |
| .cfi_rel_offset y, ((slot) + 1) * 8; \ |
| |
| #define SAVE_VEC_PAIR(x, y, slot) \ |
| stp x, y, [sp, #((slot) * 8)]; \ |
| .cfi_rel_offset x, (slot) * 8; \ |
| .cfi_rel_offset y, ((slot) + 2) * 8; \ |
| |
| #define RESTORE_REG(x, slot) \ |
| ldr x, [sp, #((slot) * 8)]; \ |
| .cfi_restore x; \ |
| |
| #define RESTORE_REG_PAIR(x, y, slot) \ |
| ldp x, y, [sp, #((slot) * 8)]; \ |
| .cfi_restore x; \ |
| .cfi_restore y; \ |
| |
| // On entry, x0 is the address of a TlsDynamicResolverArg object rather than |
| // the TlsDescriptor address passed to the original resolver function. |
| ENTRY_PRIVATE(tlsdesc_resolver_dynamic_slow_path) |
| sub sp, sp, #(8 * 84) |
| .cfi_def_cfa_offset (8 * 84) |
| SAVE_GPR_PAIR(x29, x30, 0) |
| mov x29, sp |
| |
| // Avoid leaking the contents of the shadow call stack register (x18) into |
| // memory. x19 through x29 are callee-save registers, so we do not need to |
| // save them. |
| SAVE_GPR_PAIR(x1, x2, 2) |
| SAVE_GPR_PAIR(x3, x4, 4) |
| SAVE_GPR_PAIR(x5, x6, 6) |
| SAVE_GPR_PAIR(x7, x8, 8) |
| SAVE_GPR_PAIR(x9, x10, 10) |
| SAVE_GPR_PAIR(x11, x12, 12) |
| SAVE_GPR_PAIR(x13, x14, 14) |
| SAVE_GPR_PAIR(x15, x16, 16) |
| SAVE_REG(x17, 18) |
| |
| SAVE_VEC_PAIR(q0, q1, 20) |
| SAVE_VEC_PAIR(q2, q3, 24) |
| SAVE_VEC_PAIR(q4, q5, 28) |
| SAVE_VEC_PAIR(q6, q7, 32) |
| SAVE_VEC_PAIR(q8, q9, 36) |
| SAVE_VEC_PAIR(q10, q11, 40) |
| SAVE_VEC_PAIR(q12, q13, 44) |
| SAVE_VEC_PAIR(q14, q15, 48) |
| SAVE_VEC_PAIR(q16, q17, 52) |
| SAVE_VEC_PAIR(q18, q19, 56) |
| SAVE_VEC_PAIR(q20, q21, 60) |
| SAVE_VEC_PAIR(q22, q23, 64) |
| SAVE_VEC_PAIR(q24, q25, 68) |
| SAVE_VEC_PAIR(q26, q27, 72) |
| SAVE_VEC_PAIR(q28, q29, 76) |
| SAVE_VEC_PAIR(q30, q31, 80) |
| |
| add x0, x0, #8 |
| bl __tls_get_addr |
| mrs x1, tpidr_el0 // __get_tls() |
| sub x0, x0, x1 |
| |
| RESTORE_REG_PAIR(q30, q31, 80) |
| RESTORE_REG_PAIR(q28, q29, 76) |
| RESTORE_REG_PAIR(q26, q27, 72) |
| RESTORE_REG_PAIR(q24, q25, 68) |
| RESTORE_REG_PAIR(q22, q23, 64) |
| RESTORE_REG_PAIR(q20, q21, 60) |
| RESTORE_REG_PAIR(q18, q19, 56) |
| RESTORE_REG_PAIR(q16, q17, 52) |
| RESTORE_REG_PAIR(q14, q15, 48) |
| RESTORE_REG_PAIR(q12, q13, 44) |
| RESTORE_REG_PAIR(q10, q11, 40) |
| RESTORE_REG_PAIR(q8, q9, 36) |
| RESTORE_REG_PAIR(q6, q7, 32) |
| RESTORE_REG_PAIR(q4, q5, 28) |
| RESTORE_REG_PAIR(q2, q3, 24) |
| RESTORE_REG_PAIR(q0, q1, 20) |
| |
| RESTORE_REG(x17, 18) |
| RESTORE_REG_PAIR(x15, x16, 16) |
| RESTORE_REG_PAIR(x13, x14, 14) |
| RESTORE_REG_PAIR(x11, x12, 12) |
| RESTORE_REG_PAIR(x9, x10, 10) |
| RESTORE_REG_PAIR(x7, x8, 8) |
| RESTORE_REG_PAIR(x5, x6, 6) |
| RESTORE_REG_PAIR(x3, x4, 4) |
| RESTORE_REG_PAIR(x1, x2, 2) |
| |
| RESTORE_REG_PAIR(x29, x30, 0) |
| add sp, sp, #(8 * 84) |
| .cfi_def_cfa_offset 0 |
| ret |
| END(tlsdesc_resolver_dynamic_slow_path) |
| |
| // The address of an unresolved weak TLS symbol evaluates to NULL with TLSDESC. |
| // The value returned by this function is added to the thread pointer, so return |
| // a negated thread pointer to cancel it out. |
| ENTRY_PRIVATE(tlsdesc_resolver_unresolved_weak) |
| str x19, [sp, #-16]! |
| .cfi_def_cfa_offset 16 |
| .cfi_rel_offset x19, 0 |
| ldr x19, [x0, #8] |
| mrs x0, tpidr_el0 // __get_tls() |
| sub x0, x19, x0 |
| ldr x19, [sp], #16 |
| .cfi_def_cfa_offset 0 |
| .cfi_restore x19 |
| ret |
| END(tlsdesc_resolver_unresolved_weak) |
