| // Copyright 2019 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| .text |
| |
| // This function is assumed to be called only from within InitGC. The value |
| // pointed to by InitGCs frame pointer is loaded as the stack sentinal value. |
| .globl InitTopOfStack |
| InitTopOfStack: |
| mov (%rbp), %rdi |
| mov %rdi, (TopOfStack) |
| ret |
| |
| .extern StackWalkAndMoveObjects |
| .globl GC |
| |
| // We place the frame pointer in the first arg slot register and call |
| // StackWalkAndMoveObjects. The function epilogue needs to be hand-written |
| // afterwards so as to not corrupt the stack. |
| GC: |
| pushq %rbp |
| movq %rsp, %rbp |
| subq $8, %rsp |
| mov %rbp, %rdi |
| call StackWalkAndMoveObjects |
| addq $8, %rsp |
| popq %rbp |
| ret |
| |
| .bss |
| .globl TopOfStack |
| TopOfStack: |
| .quad 0 |
| .size TopOfStack, 8 |
