| // Copyright 2020 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // Push all callee-saved registers to get them on the stack for conservative |
| // stack scanning. |
| // |
| // See asm/x64/push_registers_clang.cc for why the function is not generated |
| // using clang. |
| // |
| // Do not depend on V8_TARGET_OS_* defines as some embedders may override the |
| // GN toolchain (e.g. ChromeOS) and not provide them. |
| asm(".set noreorder \n" |
| ".global PushAllRegistersAndIterateStack \n" |
| ".type PushAllRegistersAndIterateStack, %function \n" |
| ".hidden PushAllRegistersAndIterateStack \n" |
| "PushAllRegistersAndIterateStack: \n" |
| // Push all callee-saved registers and save return address. |
| " addiu $sp, $sp, -48 \n" |
| " sw $ra, 44($sp) \n" |
| " sw $s8, 40($sp) \n" |
| " sw $sp, 36($sp) \n" |
| " sw $gp, 32($sp) \n" |
| " sw $s7, 28($sp) \n" |
| " sw $s6, 24($sp) \n" |
| " sw $s5, 20($sp) \n" |
| " sw $s4, 16($sp) \n" |
| " sw $s3, 12($sp) \n" |
| " sw $s2, 8($sp) \n" |
| " sw $s1, 4($sp) \n" |
| " sw $s0, 0($sp) \n" |
| // Maintain frame pointer. |
| " move $s8, $sp \n" |
| // Pass 1st parameter (a0) unchanged (Stack*). |
| // Pass 2nd parameter (a1) unchanged (StackVisitor*). |
| // Save 3rd parameter (a2; IterateStackCallback). |
| " move $a3, $a2 \n" |
| // Call the callback. |
| " jalr $a3 \n" |
| // Delay slot: Pass 3rd parameter as sp (stack pointer). |
| " move $a2, $sp \n" |
| // Load return address. |
| " lw $ra, 44($sp) \n" |
| // Restore frame pointer. |
| " lw $s8, 40($sp) \n" |
| " jr $ra \n" |
| // Delay slot: Discard all callee-saved registers. |
| " addiu $sp, $sp, 48 \n"); |
