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cppgc: Conservative stack scanning for arm32

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Bug: chromium:1056170
Change-Id: I417a0f05bcd185e969fb087a6b132e88c3fa3a5d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2129635
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67011}
This commit is contained in:
Michael Lippautz 2020-04-06 13:01:47 +02:00 committed by Commit Bot
parent 7cd01ed3c1
commit 1a7f568987
2 changed files with 41 additions and 1 deletions
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4
BUILD.gn
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@ -349,7 +349,7 @@ config("libbase_config") {
# This config should be applied to code using the cppgc_base.
config("cppgc_base_config") {
if (is_clang) {
if (target_cpu == "x64" || target_cpu == "x86") {
if (target_cpu == "x64" || target_cpu == "x86" || target_cpu == "arm") {
defines = [ "CPPGC_SUPPORTS_CONSERVATIVE_STACK_SCAN" ]
}
}
@ -3972,6 +3972,8 @@ v8_source_set("cppgc_base") {
sources += [ "src/heap/cppgc/asm/x64/push_registers_clang.cc" ]
} else if (target_cpu == "x86") {
sources += [ "src/heap/cppgc/asm/ia32/push_registers_clang.cc" ]
} else if (target_cpu == "arm") {
sources += [ "src/heap/cppgc/asm/arm/push_registers_clang.cc" ]
}
}

38
src/heap/cppgc/asm/arm/push_registers_clang.cc Normal file
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@ -0,0 +1,38 @@
// 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.
// We maintain 8-byte alignment at calls by pushing an additional
// non-callee-saved register (r3).
//
// Calling convention source:
// https://en.wikipedia.org/wiki/Calling_convention#ARM_(A32)
// http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka4127.html
asm(".globl PushAllRegistersAndIterateStack \n"
".hidden PushAllRegistersAndIterateStack \n"
"PushAllRegistersAndIterateStack: \n"
// Push all callee-saved registers and save return address.
// Only {r4-r11} are callee-saved registers. Push r3 in addition to align
// the stack back to 8 bytes.
" push {r3-r11, lr} \n"
// Pass 1st parameter (r0) unchanged (Stack*).
// Pass 2nd parameter (r1) unchanged (StackVisitor*).
// Save 3rd parameter (r2; IterateStackCallback).
" mov r3, r2 \n"
// Pass 3rd parameter as sp (stack pointer).
" mov r2, sp \n"
// Call the callback.
" blx r3 \n"
// Discard all the registers.
" add sp, sp, #36 \n"
// Pop lr into pc which returns and switches mode if needed.
" pop {pc} \n");