[JAEGER] Remove VMFrame::scriptedReturn (bug 587833, r=dmandelin).

This commit is contained in:
David Anderson 2010-08-19 13:34:06 -04:00
parent f3a2844e1b
commit d1f08da7e5
7 changed files with 229 additions and 124 deletions

View File

@ -167,21 +167,25 @@ mjit::TryCompile(JSContext *cx, JSScript *script, JSFunction *fun, JSObject *sco
return status;
}
void
mjit::Compiler::saveReturnAddress()
{
#ifndef JS_CPU_ARM
masm.pop(Registers::ReturnReg);
restoreFrameRegs(masm);
masm.storePtr(Registers::ReturnReg, Address(JSFrameReg, offsetof(JSStackFrame, ncode)));
#else
restoreFrameRegs(masm);
masm.storePtr(JSC::ARMRegisters::lr, Address(JSFrameReg, offsetof(JSStackFrame, ncode)));
#endif
}
CompileStatus
mjit::Compiler::generatePrologue()
{
invokeLabel = masm.label();
#ifdef JS_CPU_ARM
/*
* Unlike x86/x64, the return address is not automatically pushed onto the stack during a call
* (blx). To compensate, we explicitly push it here.
*
* NOTE: The ABI requires that we maintain 8-byte stack alignment at function boundaries. The
* trampoline always enters this function with an unaligned stack so we can re-align it.
*/
masm.push(JSC::ARMRegisters::lr);
#endif
restoreFrameRegs(masm);
saveReturnAddress();
/*
* If there is no function, then this can only be called via JaegerShot(),
@ -190,10 +194,7 @@ mjit::Compiler::generatePrologue()
if (fun) {
Jump j = masm.jump();
invokeLabel = masm.label();
#ifdef JS_CPU_ARM
masm.push(JSC::ARMRegisters::lr);
#endif
restoreFrameRegs(masm);
saveReturnAddress();
/* Set locals to undefined. */
for (uint32 i = 0; i < script->nslots; i++) {
@ -1572,6 +1573,16 @@ mjit::Compiler::jsop_getglobal(uint32 index)
frame.push(address);
}
void
mjit::Compiler::restoreReturnAddress(Assembler &masm)
{
#ifndef JS_CPU_ARM
masm.push(Address(JSFrameReg, offsetof(JSStackFrame, ncode)));
#else
masm.move(Address(JSFrameReg, offsetof(JSStackFrame, ncode)), JSC::ARMRegisters::lr);
#endif
}
void
mjit::Compiler::emitReturn()
{
@ -1583,6 +1594,7 @@ mjit::Compiler::emitReturn()
FrameAddress(offsetof(VMFrame, entryFp)),
JSFrameReg);
stubcc.linkExit(noInlineCalls, Uses(frame.frameDepth()));
restoreReturnAddress(stubcc.masm);
stubcc.masm.ret();
JS_ASSERT_IF(!fun, JSOp(*PC) == JSOP_STOP);
@ -1643,13 +1655,12 @@ mjit::Compiler::emitReturn()
Address rval(JSFrameReg, JSStackFrame::offsetReturnValue());
masm.loadPayload(rval, JSReturnReg_Data);
masm.loadTypeTag(rval, JSReturnReg_Type);
restoreReturnAddress(masm);
masm.move(Registers::ReturnReg, JSFrameReg);
masm.loadPtr(Address(JSFrameReg, offsetof(JSStackFrame, ncode)), Registers::ReturnReg);
#ifdef DEBUG
masm.storePtr(ImmPtr(JSStackFrame::sInvalidPC),
Address(JSFrameReg, offsetof(JSStackFrame, savedPC)));
#endif
masm.ret();
}
@ -1836,20 +1847,12 @@ mjit::Compiler::inlineCallHelper(uint32 argc, bool callingNew)
}
/* Fast-path: return address contains scripted call. */
masm.addPtr(Imm32(sizeof(void*)), Registers::StackPointer);
masm.call(Registers::ReturnReg);
#if defined(JS_NO_FASTCALL) && defined(JS_CPU_X86)
masm.callLabel = masm.label();
#endif
ADD_CALLSITE(false);
/*
* The scripted call returns a register triplet, containing the jsval and
* the current f.scriptedReturn.
*/
masm.push(Registers::ReturnReg);
/*
* Functions invoked with |new| can return, for some reason, primitive
* values. Just deal with this here.

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@ -225,6 +225,8 @@ class Compiler
void addCallSite(uint32 id, bool stub);
/* Emitting helpers. */
void saveReturnAddress();
void restoreReturnAddress(Assembler &masm);
void restoreFrameRegs(Assembler &masm);
void emitStubCmpOp(BoolStub stub, jsbytecode *target, JSOp fused);
void iter(uintN flags);

View File

@ -169,7 +169,6 @@ top:
static inline void
FixVMFrame(VMFrame &f, JSStackFrame *fp)
{
f.fp->ncode = f.scriptedReturn;
JS_ASSERT(f.fp == fp->down);
f.fp = fp;
}
@ -500,7 +499,6 @@ CreateLightFrame(VMFrame &f, uint32 flags, uint32 argc)
}
/* Initialize the frame. */
newfp->ncode = NULL;
newfp->setCallObj(NULL);
newfp->setArgsObj(NULL);
newfp->setScript(newscript);
@ -634,7 +632,6 @@ js_InternalThrow(VMFrame &f)
JS_ASSERT(f.regs.sp == cx->regs->sp);
InlineReturn(f, JS_FALSE);
f.scriptedReturn = cx->fp->ncode;
}
JS_ASSERT(f.regs.sp == cx->regs->sp);
@ -768,7 +765,8 @@ RemoveExcessFrames(VMFrame &f, JSStackFrame *entryFrame)
fp->flags &= ~JSFRAME_RECORDING;
if (AtSafePoint(cx)) {
if (!JaegerShot(cx)) {
JSScript *script = fp->getScript();
if (!JaegerShotAtSafePoint(cx, script->nmap[cx->regs->pc - script->code])) {
if (!SwallowErrors(f, entryFrame))
return false;
@ -846,9 +844,6 @@ RunTracer(VMFrame &f)
if (!cx->jitEnabled)
return NULL;
JS_ASSERT_IF(f.fp != f.entryFp,
entryFrame->down->getScript()->isValidJitCode(f.scriptedReturn));
bool blacklist;
uintN inlineCallCount = 0;
tpa = MonitorTracePoint(f.cx, inlineCallCount, blacklist);
@ -884,9 +879,12 @@ RunTracer(VMFrame &f)
* The tracer could have dropped us off on any frame at any position.
* Well, it could not have removed frames (recursion is disabled).
*
* Frames after the entryFrame cannot be entered via JaegerShot()
* unless each is at a safe point. We can JaegerShot these frames
* individually, but we must unwind to the entryFrame.
* Frames after the entryFrame cannot be entered via JaegerShotAtSafePoint()
* unless each is at a safe point. We can JaegerShotAtSafePoint these
* frames individually, but we must unwind to the entryFrame.
*
* Note carefully that JaegerShotAtSafePoint can resume methods at
* arbitrary safe points whereas JaegerShot cannot.
*
* If we land on entryFrame without a safe point in sight, we'll end up
* at the RETURN op. This is an edge case with two paths:
@ -895,10 +893,8 @@ RunTracer(VMFrame &f)
* move the return value down.
* 2) The entryFrame is NOT the last inline frame. Pop the frame.
*
* In both cases, we hijack the stub to return to JaegerFromTracer. This
* moves |oldFp->rval| into the scripted return registers, places the
* new f.scriptedReturn in the machine return register, and returns to its
* caller safely.
* In both cases, we hijack the stub to return to InjectJaegerReturn. This
* moves |oldFp->rval| into the scripted return registers.
*/
restart:
@ -936,8 +932,7 @@ RunTracer(VMFrame &f)
if (!InlineReturn(f, JS_TRUE))
THROWV(NULL);
}
entryFrame->ncode = f.fp->ncode;
void *retPtr = JS_FUNC_TO_DATA_PTR(void *, JaegerFromTracer);
void *retPtr = JS_FUNC_TO_DATA_PTR(void *, InjectJaegerReturn);
*f.returnAddressLocation() = retPtr;
return NULL;
}

View File

@ -49,6 +49,56 @@
using namespace js;
using namespace js::mjit;
/*
* Explanation of VMFrame activation and various helper thunks below.
*
* JaegerTrampoline - Executes a method JIT-compiled JSFunction. This function
* creates a VMFrame on the machine stack and calls into JIT'd code. The JIT'd
* code will eventually return to the VMFrame.
*
* - Called from C++ functions JaegerShot and JaegerBomb.
* - Parameters: cx, fp, code, stackLimit, safePoint
* - Notes: safePoint is used in combination with SafePointTrampoline,
* explained further down.
*
* JaegerThrowpoline - Calls into an exception handler from JIT'd code, and if a
* scripted exception handler is not found, unwinds the VMFrame and returns
* to C++.
*
* - To start exception handling, we return from a stub call to the throwpoline.
* - On entry to the throwpoline, the normal conditions of the jit-code ABI
* are satisfied.
* - To do the unwinding and find out where to continue executing, we call
* js_InternalThrow.
* - js_InternalThrow may return 0, which means the place to continue, if any,
* is above this JaegerShot activation, so we just return, in the same way
* the trampoline does.
* - Otherwise, js_InternalThrow returns a jit-code address to continue
* execution
* at. Because the jit-code ABI conditions are satisfied, we can just jump
* to that point.
*
*
* SafePointTrampoline - Inline script calls link their return addresses through
* JSStackFrame::ncode. This includes the return address that unwinds back
* to JaegerTrampoline. However, the tracer integration code often wants to
* enter a method JIT'd function at an arbitrary safe point. Safe points
* do not have the return address linking code that the method prologue has.
* SafePointTrampoline is a thunk which correctly links the initial return
* address. It is used in JaegerBomb, and passed as the "script code"
* parameter. Using the "safePoint" parameter to JaegerTrampoline, it correctly
* jumps to the intended point in the method.
*
* - Used by JaegerTrampoline()
*
* InjectJaegerReturn - Implements the tail of InlineReturn. This is needed for
* tracer integration, where a "return" opcode might not be a safe-point,
* and thus the return path must be injected by hijacking the stub return
* address.
*
* - Used by RunTracer()
*/
#ifdef JS_METHODJIT_PROFILE_STUBS
static const size_t STUB_CALLS_FOR_OP_COUNT = 255;
static uint32 StubCallsForOp[STUB_CALLS_FOR_OP_COUNT];
@ -150,27 +200,32 @@ SYMBOL_STRING(JaegerTrampoline) ":" "\n"
"movq %rsi, %rbx" "\n"
/* Space for the rest of the VMFrame. */
"subq $0x30, %rsp" "\n"
"subq $0x28, %rsp" "\n"
/* Set cx->regs and set the active frame (requires saving rdx). */
/*
* This is actually part of the VMFrame, but we need to save |r8| for
* SafePointTrampoline.
*/
"pushq %r8" "\n"
/* Set cx->regs and set the active frame. Save rdx and align frame in one. */
"pushq %rdx" "\n"
"movq %rsp, %rdi" "\n"
"call " SYMBOL_STRING_RELOC(SetVMFrameRegs) "\n"
"movq %rsp, %rdi" "\n"
"call " SYMBOL_STRING_RELOC(PushActiveVMFrame) "\n"
"popq %rdx" "\n"
/*
* Jump into into the JIT'd code. The call implicitly fills in
* the precious f.scriptedReturn member of VMFrame.
*/
"call *%rdx" "\n"
"leaq -8(%rsp), %rdi" "\n"
"call *0(%rsp)" "\n"
"movq %rsp, %rdi" "\n"
"call " SYMBOL_STRING_RELOC(PopActiveVMFrame) "\n"
"leaq -8(%rsp), %rdi" "\n"
"movq %rsp, %rdi" "\n"
"call " SYMBOL_STRING_RELOC(UnsetVMFrameRegs) "\n"
"addq $0x50, %rsp" "\n"
"addq $0x58, %rsp" "\n"
"popq %rbx" "\n"
"popq %r15" "\n"
"popq %r14" "\n"
@ -212,8 +267,17 @@ JS_STATIC_ASSERT(JSVAL_PAYLOAD_MASK == 0x00007FFFFFFFFFFFLL);
asm volatile (
".text\n"
".globl " SYMBOL_STRING(JaegerFromTracer) "\n"
SYMBOL_STRING(JaegerFromTracer) ":" "\n"
".globl " SYMBOL_STRING(SafePointTrampoline) "\n"
SYMBOL_STRING(SafePointTrampoline) ":" "\n"
"popq %rax" "\n"
"movq %rax, 0x60(%rbx)" "\n"
"jmp *8(%rsp)" "\n"
);
asm volatile (
".text\n"
".globl " SYMBOL_STRING(InjectJaegerReturn) "\n"
SYMBOL_STRING(InjectJaegerReturn) ":" "\n"
"movq 0x40(%rbx), %rcx" "\n" /* fp->rval type (as value) */
"movq $0xFFFF800000000000, %r11" "\n" /* load type mask (JSVAL_TAG_MASK) */
"andq %r11, %rcx" "\n" /* extract type */
@ -224,6 +288,7 @@ SYMBOL_STRING(JaegerFromTracer) ":" "\n"
"movq 0x60(%rbx), %rax" "\n" /* fp->ncode */
"movq 0x38(%rsp), %rbx" "\n" /* f.fp */
"pushq %rax" "\n"
"ret" "\n"
);
@ -253,28 +318,26 @@ SYMBOL_STRING(JaegerTrampoline) ":" "\n"
/* Build the JIT frame. Push fields in order,
* then align the stack to form esp == VMFrame. */
"movl 12(%ebp), %ebx" "\n" /* fp */
"movl 12(%ebp), %ebx" "\n" /* load fp */
"pushl %ebx" "\n" /* entryFp */
"pushl 20(%ebp)" "\n" /* inlineCallCount */
"pushl 8(%ebp)" "\n"
"pushl %ebx" "\n"
"subl $0x18, %esp" "\n"
"pushl 20(%ebp)" "\n" /* stackLimit */
"pushl 8(%ebp)" "\n" /* cx */
"pushl %ebx" "\n" /* fp */
"subl $0x1C, %esp" "\n"
/* Jump into the JIT'd code. */
"pushl 16(%ebp)" "\n"
"movl %esp, %ecx" "\n"
"call " SYMBOL_STRING_RELOC(SetVMFrameRegs) "\n"
"movl %esp, %ecx" "\n"
"call " SYMBOL_STRING_RELOC(PushActiveVMFrame) "\n"
"popl %edx" "\n"
"call *%edx" "\n"
"leal -4(%esp), %ecx" "\n"
"call *16(%ebp)" "\n"
"movl %esp, %ecx" "\n"
"call " SYMBOL_STRING_RELOC(PopActiveVMFrame) "\n"
"leal -4(%esp), %ecx" "\n"
"movl %esp, %ecx" "\n"
"call " SYMBOL_STRING_RELOC(UnsetVMFrameRegs) "\n"
"addl $0x28, %esp" "\n"
"addl $0x2C, %esp" "\n"
"popl %ebx" "\n"
"popl %edi" "\n"
"popl %esi" "\n"
@ -317,15 +380,29 @@ JS_STATIC_ASSERT(offsetof(VMFrame, fp) == 0x1C);
asm volatile (
".text\n"
".globl " SYMBOL_STRING(JaegerFromTracer) "\n"
SYMBOL_STRING(JaegerFromTracer) ":" "\n"
".globl " SYMBOL_STRING(InjectJaegerReturn) "\n"
SYMBOL_STRING(InjectJaegerReturn) ":" "\n"
"movl 0x28(%ebx), %edx" "\n" /* fp->rval data */
"movl 0x2C(%ebx), %ecx" "\n" /* fp->rval type */
"movl 0x3C(%ebx), %eax" "\n" /* fp->ncode */
"movl 0x1C(%esp), %ebx" "\n" /* f.fp */
"pushl %eax" "\n"
"ret" "\n"
);
/*
* Take the fifth parameter from JaegerShot() and jump to it. This makes it so
* we can jump into arbitrary JIT code, which won't have the frame-fixup prologue.
*/
asm volatile (
".text\n"
".globl " SYMBOL_STRING(SafePointTrampoline) "\n"
SYMBOL_STRING(SafePointTrampoline) ":" "\n"
"popl %eax" "\n"
"movl %eax, 0x3C(%ebx)" "\n"
"jmp *24(%ebp)" "\n"
);
# elif defined(JS_CPU_ARM)
JS_STATIC_ASSERT(sizeof(VMFrame) == 80);
@ -337,16 +414,30 @@ JS_STATIC_ASSERT(offsetof(VMFrame, fp) == (4*7));
JS_STATIC_ASSERT(offsetof(VMFrame, oldRegs) == (4*4));
JS_STATIC_ASSERT(offsetof(VMFrame, previous) == (4*3));
JS_STATIC_ASSERT(offsetof(VMFrame, scriptedReturn) == (4*0));
JS_STATIC_ASSERT(offsetof(JSStackFrame, ncode) == 60);
JS_STATIC_ASSERT(offsetof(JSStackFrame, rval) == 40);
asm volatile (
".text\n"
".globl " SYMBOL_STRING(JaegerFromTracer) "\n"
SYMBOL_STRING(JaegerFromTracer) ":" "\n"
".globl " SYMBOL_STRING(InjectJaegerReturn) "\n"
SYMBOL_STRING(InjectJaegerReturn) ":" "\n"
/* Restore frame regs. */
"ldr r11, [sp, #32]" "\n"
"ldr r1, [r11, #40]" "\n" /* fp->rval data */
"ldr r2, [r11, #44]" "\n" /* fp->rval type */
"ldr r0, [r11, #60]" "\n" /* fp->ncode */
"ldr r11, [sp, #28]" "\n" /* load f.fp */
"bx r0" "\n"
);
asm volatile (
".text\n"
".globl " SYMBOL_STRING(SafePointTrampoline) "\n"
SYMBOL_STRING(SafePointTrampoline) ":"
"str lr, [r11, #60]" "\n"
/* This should load the fifth parameter from JaegerTrampoline and jump to it. */
"" "\n"
);
asm volatile (
".text\n"
".globl " SYMBOL_STRING(JaegerTrampoline) "\n"
@ -399,11 +490,8 @@ SYMBOL_STRING(JaegerTrampoline) ":" "\n"
" mov r0, sp" "\n"
" bl " SYMBOL_STRING_RELOC(PushActiveVMFrame)"\n"
/* Call the compiled JavaScript function. We do this with an unaligned sp because the compiled
* script explicitly pushes the return value into f->scriptedReturn. */
" add sp, sp, #(4*1)" "\n"
/* Call the compiled JavaScript function. */
" blx r4" "\n"
" sub sp, sp, #(4*1)" "\n"
/* Tidy up. */
" mov r0, sp" "\n"
@ -473,19 +561,29 @@ JS_STATIC_ASSERT(offsetof(VMFrame, fp) == 0x1C);
extern "C" {
__declspec(naked) void JaegerFromTracer()
__declspec(naked) void InjectJaegerReturn()
{
__asm {
mov edx, [ebx + 0x28];
mov ecx, [ebx + 0x2C];
mov eax, [ebx + 0x3C];
mov ebx, [esp + 0x1C];
push eax;
ret;
}
}
__declspec(naked) void SafePointTrampoline()
{
__asm {
pop eax;
mov eax, [ebx + 0x3C];
jmp [ebp + 24];
}
}
__declspec(naked) JSBool JaegerTrampoline(JSContext *cx, JSStackFrame *fp, void *code,
Value *stackLimit)
Value *stackLimit, void *safePoint)
{
__asm {
/* Prologue. */
@ -503,23 +601,21 @@ extern "C" {
push [ebp + 20];
push [ebp + 8];
push ebx;
sub esp, 0x18;
sub esp, 0x1C;
/* Jump into into the JIT'd code. */
push [ebp+16];
mov ecx, esp;
call SetVMFrameRegs;
mov ecx, esp;
call PushActiveVMFrame;
pop edx;
call edx;
lea ecx, [esp-4];
call [ebp + 16];
mov ecx, esp;
call PopActiveVMFrame;
lea ecx, [esp-4];
mov ecx, esp;
call UnsetVMFrameRegs;
add esp, 0x28
add esp, 0x2C;
pop ebx;
pop edi;
@ -618,39 +714,22 @@ ThreadData::Finish()
}
extern "C" JSBool JaegerTrampoline(JSContext *cx, JSStackFrame *fp, void *code,
Value *stackLimit);
Value *stackLimit, void *safePoint);
extern "C" void SafePointTrampoline();
JSBool
mjit::JaegerShot(JSContext *cx)
static inline JSBool
EnterMethodJIT(JSContext *cx, JSStackFrame *fp, void *code, void *safePoint)
{
JS_ASSERT(cx->regs);
JS_CHECK_RECURSION(cx, return JS_FALSE;);
void *code;
jsbytecode *pc = cx->regs->pc;
JSStackFrame *fp = cx->fp;
JSScript *script = fp->getScript();
JS_ASSERT(script->ncode && script->ncode != JS_UNJITTABLE_METHOD);
#ifdef JS_TRACER
if (TRACE_RECORDER(cx))
AbortRecording(cx, "attempt to enter method JIT while recording");
#endif
if (pc == script->code)
code = script->nmap[-1];
else
code = script->nmap[pc - script->code];
JS_ASSERT(code);
#ifdef JS_METHODJIT_SPEW
Profiler prof;
JSScript *script = fp->getScript();
JaegerSpew(JSpew_Prof, "entering jaeger script: %s, line %d\n", script->filename,
script->lineno);
JaegerSpew(JSpew_Prof, "%s jaeger script: %s, line %d\n",
safePoint ? "dropping" : "entering",
script->filename, script->lineno);
prof.start();
#endif
@ -661,7 +740,7 @@ mjit::JaegerShot(JSContext *cx)
Value *stackLimit = cx->stack().makeStackLimit(reinterpret_cast<Value*>(fp));
JSAutoResolveFlags rf(cx, JSRESOLVE_INFER);
JSBool ok = JaegerTrampoline(cx, fp, code, stackLimit);
JSBool ok = JaegerTrampoline(cx, fp, code, stackLimit, safePoint);
JS_ASSERT(checkFp == cx->fp);
@ -673,6 +752,37 @@ mjit::JaegerShot(JSContext *cx)
return ok;
}
JSBool
mjit::JaegerShot(JSContext *cx)
{
JSScript *script = cx->fp->getScript();
JS_ASSERT(script->ncode && script->ncode != JS_UNJITTABLE_METHOD);
#ifdef JS_TRACER
if (TRACE_RECORDER(cx))
AbortRecording(cx, "attempt to enter method JIT while recording");
#endif
JS_ASSERT(cx->regs->pc == script->code);
void *code = script->nmap[-1];
return EnterMethodJIT(cx, cx->fp, code, NULL);
}
JSBool
js::mjit::JaegerShotAtSafePoint(JSContext *cx, void *safePoint)
{
#ifdef JS_TRACER
JS_ASSERT(!TRACE_RECORDER(cx));
#endif
void *code = JS_FUNC_TO_DATA_PTR(void *, SafePointTrampoline);
return EnterMethodJIT(cx, cx->fp, code, safePoint);
}
template <typename T>
static inline void Destroy(T &t)
{
@ -720,13 +830,6 @@ mjit::ReleaseScriptCode(JSContext *cx, JSScript *script)
script->mics = NULL;
}
#endif
# if 0 /* def JS_TRACER */
if (script->trees) {
cx->free(script->trees);
script->trees = NULL;
}
# endif
}
#ifdef JS_METHODJIT_PROFILE_STUBS

View File

@ -57,13 +57,11 @@ namespace js {
struct VMFrame
{
/* This must be the first entry on CPUs which push return addresses. */
void *scriptedReturn;
union Arguments {
struct {
void *ptr;
void *ptr2;
void *ptr3;
} x;
} u;
@ -173,8 +171,11 @@ typedef void (JS_FASTCALL *VoidStubPC)(VMFrame &, jsbytecode *);
namespace mjit {
JSBool
JaegerShot(JSContext *cx);
/* Execute a method that has been JIT compiled. */
JSBool JaegerShot(JSContext *cx);
/* Drop into the middle of a method at an arbitrary point, and execute. */
JSBool JaegerShotAtSafePoint(JSContext *cx, void *safePoint);
enum CompileStatus
{
@ -224,7 +225,7 @@ extern "C" void *JaegerThrowpoline(js::VMFrame *vmFrame);
#else
extern "C" void JaegerThrowpoline();
#endif
extern "C" void JaegerFromTracer();
extern "C" void InjectJaegerReturn();
#endif /* jsjaeger_h__ */

View File

@ -136,11 +136,6 @@ Recompiler::recompile()
f != NULL;
f = f->previous) {
if (script->isValidJitCode(f->scriptedReturn)) {
if (!toPatch.append(findPatch(&f->scriptedReturn)))
return false;
}
void **machineReturn = f->returnAddressLocation();
if (script->isValidJitCode(*machineReturn)) {
if (!toPatch.append(findPatch(machineReturn)))

View File

@ -137,8 +137,14 @@ TrampolineCompiler::generateForceReturn(Assembler &masm)
Address rval(JSFrameReg, JSStackFrame::offsetReturnValue());
masm.loadPayload(rval, JSReturnReg_Data);
masm.loadTypeTag(rval, JSReturnReg_Type);
#ifndef JS_CPU_ARM
masm.push(Address(JSFrameReg, offsetof(JSStackFrame, ncode)));
#else
masm.move(Address(JSFrameReg, offsetof(JSStackFrame, ncode)), JSC::ARMRegisters::lr);
#endif
masm.move(Registers::ReturnReg, JSFrameReg);
masm.loadPtr(Address(JSFrameReg, offsetof(JSStackFrame, ncode)), Registers::ReturnReg);
#ifdef DEBUG
masm.storePtr(ImmPtr(JSStackFrame::sInvalidPC),
Address(JSFrameReg, offsetof(JSStackFrame, savedPC)));