Merge the jsCStack branch
https://bugs.webkit.org/show_bug.cgi?id=127763
Reviewed by Mark Hahnenberg.
Source/JavaScriptCore:
Changes from http://svn.webkit.org/repository/webkit/branches/jsCStack
up to changeset 162958.
Source/WebCore:
Changes from http://svn.webkit.org/repository/webkit/branches/jsCStack
up to changeset 162958.
Source/WTF:
Changes from http://svn.webkit.org/repository/webkit/branches/jsCStack
up to changeset 162958.
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@163027 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp b/Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp
index 076a495..a855c9d 100644
--- a/Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp
+++ b/Source/JavaScriptCore/ftl/FTLOSRExitCompiler.cpp
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2013 Apple Inc. All rights reserved.
+ * Copyright (C) 2013, 2014 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -34,8 +34,10 @@
#include "FTLJITCode.h"
#include "FTLOSRExit.h"
#include "FTLSaveRestore.h"
+#include "MaxFrameExtentForSlowPathCall.h"
#include "OperandsInlines.h"
#include "Operations.h"
+#include "RegisterPreservationWrapperGenerator.h"
#include "RepatchBuffer.h"
namespace JSC { namespace FTL {
@@ -62,9 +64,10 @@
// We need scratch space to save all registers and to build up the JSStack.
// Use a scratch buffer to transfer all values.
- ScratchBuffer* scratchBuffer = vm->scratchBufferForSize(sizeof(EncodedJSValue) * exit.m_values.size() + requiredScratchMemorySizeInBytes());
+ ScratchBuffer* scratchBuffer = vm->scratchBufferForSize(sizeof(EncodedJSValue) * exit.m_values.size() + requiredScratchMemorySizeInBytes() + jitCode->unwindInfo.m_registers.size() * sizeof(uint64_t));
EncodedJSValue* scratch = scratchBuffer ? static_cast<EncodedJSValue*>(scratchBuffer->dataBuffer()) : 0;
char* registerScratch = bitwise_cast<char*>(scratch + exit.m_values.size());
+ uint64_t* unwindScratch = bitwise_cast<uint64_t*>(registerScratch + requiredScratchMemorySizeInBytes());
// Make sure that saveAllRegisters() has a place on top of the stack to spill things. That
// function expects to be able to use top of stack for scratch memory.
@@ -75,18 +78,27 @@
jit.pop(GPRInfo::regT0);
jit.pop(GPRInfo::regT0);
+ if (vm->m_perBytecodeProfiler && codeBlock->jitCode()->dfgCommon()->compilation) {
+ Profiler::Database& database = *vm->m_perBytecodeProfiler;
+ Profiler::Compilation* compilation = codeBlock->jitCode()->dfgCommon()->compilation.get();
+
+ Profiler::OSRExit* profilerExit = compilation->addOSRExit(
+ exitID, Profiler::OriginStack(database, codeBlock, exit.m_codeOrigin),
+ exit.m_kind, isWatchpoint(exit.m_kind));
+ jit.add64(CCallHelpers::TrustedImm32(1), CCallHelpers::AbsoluteAddress(profilerExit->counterAddress()));
+ }
+
// The remaining code assumes that SP/FP are in the same state that they were in the FTL's
// call frame.
// Get the call frame and tag thingies.
// Restore the exiting function's callFrame value into a regT4
- record->locations[0].restoreInto(jit, jitCode->stackmaps, registerScratch, GPRInfo::regT4);
jit.move(MacroAssembler::TrustedImm64(TagTypeNumber), GPRInfo::tagTypeNumberRegister);
jit.move(MacroAssembler::TrustedImm64(TagMask), GPRInfo::tagMaskRegister);
// Do some value profiling.
if (exit.m_profileValueFormat != InvalidValueFormat) {
- record->locations[1].restoreInto(jit, jitCode->stackmaps, registerScratch, GPRInfo::regT0);
+ record->locations[0].restoreInto(jit, jitCode->stackmaps, registerScratch, GPRInfo::regT0);
reboxAccordingToFormat(
exit.m_profileValueFormat, jit, GPRInfo::regT0, GPRInfo::regT1, GPRInfo::regT2);
@@ -130,7 +142,45 @@
case ExitValueInJSStackAsInt32:
case ExitValueInJSStackAsInt52:
case ExitValueInJSStackAsDouble:
- jit.load64(AssemblyHelpers::addressFor(value.virtualRegister(), GPRInfo::regT4), GPRInfo::regT0);
+ jit.load64(AssemblyHelpers::addressFor(value.virtualRegister()), GPRInfo::regT0);
+ break;
+
+ case ExitValueRecovery:
+ record->locations[value.rightRecoveryArgument()].restoreInto(
+ jit, jitCode->stackmaps, registerScratch, GPRInfo::regT1);
+ record->locations[value.leftRecoveryArgument()].restoreInto(
+ jit, jitCode->stackmaps, registerScratch, GPRInfo::regT0);
+ switch (value.recoveryOpcode()) {
+ case AddRecovery:
+ switch (value.recoveryFormat()) {
+ case ValueFormatInt32:
+ jit.add32(GPRInfo::regT1, GPRInfo::regT0);
+ break;
+ case ValueFormatInt52:
+ jit.add64(GPRInfo::regT1, GPRInfo::regT0);
+ break;
+ default:
+ RELEASE_ASSERT_NOT_REACHED();
+ break;
+ }
+ break;
+ case SubRecovery:
+ switch (value.recoveryFormat()) {
+ case ValueFormatInt32:
+ jit.sub32(GPRInfo::regT1, GPRInfo::regT0);
+ break;
+ case ValueFormatInt52:
+ jit.sub64(GPRInfo::regT1, GPRInfo::regT0);
+ break;
+ default:
+ RELEASE_ASSERT_NOT_REACHED();
+ break;
+ }
+ break;
+ default:
+ RELEASE_ASSERT_NOT_REACHED();
+ break;
+ }
break;
default:
@@ -141,6 +191,137 @@
jit.store64(GPRInfo::regT0, scratch + index);
}
+ // Henceforth we make it look like the exiting function was called through a register
+ // preservation wrapper. This implies that FP must be nudged down by a certain amount. Then
+ // we restore the various things according to either exit.m_values or by copying from the
+ // old frame, and finally we save the various callee-save registers into where the
+ // restoration thunk would restore them from.
+
+ ptrdiff_t offset = registerPreservationOffset();
+ RegisterSet toSave = registersToPreserve();
+
+ // Before we start messing with the frame, we need to set aside any registers that the
+ // FTL code was preserving.
+ for (unsigned i = jitCode->unwindInfo.m_registers.size(); i--;) {
+ RegisterAtOffset entry = jitCode->unwindInfo.m_registers[i];
+ jit.load64(
+ MacroAssembler::Address(MacroAssembler::framePointerRegister, entry.offset()),
+ GPRInfo::regT0);
+ jit.store64(GPRInfo::regT0, unwindScratch + i);
+ }
+
+ jit.load32(CCallHelpers::payloadFor(JSStack::ArgumentCount), GPRInfo::regT2);
+
+ // Let's say that the FTL function had failed its arity check. In that case, the stack will
+ // contain some extra stuff.
+ //
+ // First we compute the padded stack space:
+ //
+ // paddedStackSpace = roundUp(codeBlock->numParameters - regT2 + 1)
+ //
+ // The stack will have regT2 + CallFrameHeaderSize stuff, but above it there will be
+ // paddedStackSpace gunk used by the arity check fail restoration thunk. When that happens
+ // we want to make the stack look like this, from higher addresses down:
+ //
+ // - register preservation return PC
+ // - preserved registers
+ // - arity check fail return PC
+ // - argument padding
+ // - actual arguments
+ // - call frame header
+ //
+ // So that the actual call frame header appears to return to the arity check fail return
+ // PC, and that then returns to the register preservation thunk. The arity check thunk that
+ // we return to will have the padding size encoded into it. It will then know to return
+ // into the register preservation thunk, which uses the argument count to figure out where
+ // registers are preserved.
+
+ // This code assumes that we're dealing with FunctionCode.
+ RELEASE_ASSERT(codeBlock->codeType() == FunctionCode);
+
+ jit.add32(
+ MacroAssembler::TrustedImm32(-codeBlock->numParameters()), GPRInfo::regT2,
+ GPRInfo::regT3);
+ MacroAssembler::Jump arityIntact = jit.branchTest32(MacroAssembler::Zero, GPRInfo::regT3);
+ jit.neg32(GPRInfo::regT3);
+ jit.add32(MacroAssembler::TrustedImm32(1 + stackAlignmentRegisters() - 1), GPRInfo::regT3);
+ jit.and32(MacroAssembler::TrustedImm32(-stackAlignmentRegisters()), GPRInfo::regT3);
+ jit.add32(GPRInfo::regT3, GPRInfo::regT2);
+ arityIntact.link(&jit);
+
+ // First set up SP so that our data doesn't get clobbered by signals.
+ jit.addPtr(
+ MacroAssembler::TrustedImm32(
+ WTF::roundUpToMultipleOf(
+ stackAlignmentRegisters(),
+ -registerPreservationOffset() - exit.m_values.numberOfLocals() * sizeof(Register) - maxFrameExtentForSlowPathCall)),
+ MacroAssembler::framePointerRegister, MacroAssembler::stackPointerRegister);
+
+ jit.subPtr(
+ MacroAssembler::TrustedImm32(registerPreservationOffset()),
+ MacroAssembler::framePointerRegister);
+
+ // Copy the old frame data into its new location.
+ jit.add32(MacroAssembler::TrustedImm32(JSStack::CallFrameHeaderSize), GPRInfo::regT2);
+ jit.move(MacroAssembler::framePointerRegister, GPRInfo::regT1);
+ MacroAssembler::Label loop = jit.label();
+ jit.sub32(MacroAssembler::TrustedImm32(1), GPRInfo::regT2);
+ jit.load64(MacroAssembler::Address(GPRInfo::regT1, offset), GPRInfo::regT0);
+ jit.store64(GPRInfo::regT0, GPRInfo::regT1);
+ jit.addPtr(MacroAssembler::TrustedImm32(sizeof(Register)), GPRInfo::regT1);
+ jit.branchTest32(MacroAssembler::NonZero, GPRInfo::regT2).linkTo(loop, &jit);
+
+ // At this point regT1 points to where we would save our registers. Save them here.
+ ptrdiff_t currentOffset = 0;
+ for (GPRReg gpr = AssemblyHelpers::firstRegister(); gpr <= AssemblyHelpers::lastRegister(); gpr = static_cast<GPRReg>(gpr + 1)) {
+ if (!toSave.get(gpr))
+ continue;
+ currentOffset += sizeof(Register);
+ unsigned unwindIndex = jitCode->unwindInfo.indexOf(gpr);
+ if (unwindIndex == UINT_MAX) {
+ // The FTL compilation didn't preserve this register. This means that it also
+ // didn't use the register. So its value at the beginning of OSR exit should be
+ // preserved by the thunk. Luckily, we saved all registers into the register
+ // scratch buffer, so we can restore them from there.
+ jit.load64(registerScratch + offsetOfGPR(gpr), GPRInfo::regT0);
+ } else {
+ // The FTL compilation preserved the register. Its new value is therefore
+ // irrelevant, but we can get the value that was preserved by using the unwind
+ // data. We've already copied all unwind-able preserved registers into the unwind
+ // scratch buffer, so we can get it from there.
+ jit.load64(unwindScratch + unwindIndex, GPRInfo::regT0);
+ }
+ jit.store64(GPRInfo::regT0, AssemblyHelpers::Address(GPRInfo::regT1, currentOffset));
+ }
+
+ // We need to make sure that we return into the register restoration thunk. This works
+ // differently depending on whether or not we had arity issues.
+ MacroAssembler::Jump arityIntactForReturnPC =
+ jit.branchTest32(MacroAssembler::Zero, GPRInfo::regT3);
+
+ // The return PC in the call frame header points at exactly the right arity restoration
+ // thunk. We don't want to change that. But the arity restoration thunk's frame has a
+ // return PC and we want to reroute that to our register restoration thunk. The arity
+ // restoration's return PC just just below regT1, and the register restoration's return PC
+ // is right at regT1.
+ jit.loadPtr(MacroAssembler::Address(GPRInfo::regT1, -static_cast<ptrdiff_t>(sizeof(Register))), GPRInfo::regT0);
+ jit.storePtr(GPRInfo::regT0, GPRInfo::regT1);
+ jit.storePtr(
+ MacroAssembler::TrustedImmPtr(vm->getCTIStub(registerRestorationThunkGenerator).code().executableAddress()),
+ MacroAssembler::Address(GPRInfo::regT1, -static_cast<ptrdiff_t>(sizeof(Register))));
+
+ MacroAssembler::Jump arityReturnPCReady = jit.jump();
+
+ arityIntactForReturnPC.link(&jit);
+
+ jit.loadPtr(MacroAssembler::Address(MacroAssembler::framePointerRegister, CallFrame::returnPCOffset()), GPRInfo::regT0);
+ jit.storePtr(GPRInfo::regT0, GPRInfo::regT1);
+ jit.storePtr(
+ MacroAssembler::TrustedImmPtr(vm->getCTIStub(registerRestorationThunkGenerator).code().executableAddress()),
+ MacroAssembler::Address(MacroAssembler::framePointerRegister, CallFrame::returnPCOffset()));
+
+ arityReturnPCReady.link(&jit);
+
// Now get state out of the scratch buffer and place it back into the stack. This part does
// all reboxing.
for (unsigned index = exit.m_values.size(); index--;) {
@@ -150,26 +331,16 @@
jit.load64(scratch + index, GPRInfo::regT0);
reboxAccordingToFormat(
value.valueFormat(), jit, GPRInfo::regT0, GPRInfo::regT1, GPRInfo::regT2);
- jit.store64(GPRInfo::regT0, AssemblyHelpers::addressFor(static_cast<VirtualRegister>(operand), GPRInfo::regT4));
+ jit.store64(GPRInfo::regT0, AssemblyHelpers::addressFor(static_cast<VirtualRegister>(operand)));
}
- // Restore the old stack pointer and then put regT4 into callFrameRegister. The idea is
- // that the FTL call frame is pushed onto the JS call frame and we can recover the old
- // value of the stack pointer by popping the FTL call frame. We already know what the
- // frame pointer in the JS call frame was because it would have been passed as an argument
- // to the FTL call frame.
- jit.move(MacroAssembler::framePointerRegister, MacroAssembler::stackPointerRegister);
- jit.pop(GPRInfo::nonArgGPR0);
- jit.pop(GPRInfo::nonArgGPR0);
- jit.move(GPRInfo::regT4, GPRInfo::callFrameRegister);
-
handleExitCounts(jit, exit);
reifyInlinedCallFrames(jit, exit);
adjustAndJumpToTarget(jit, exit);
LinkBuffer patchBuffer(*vm, &jit, codeBlock);
exit.m_code = FINALIZE_CODE_IF(
- shouldShowDisassembly(),
+ shouldShowDisassembly() || Options::verboseOSR(),
patchBuffer,
("FTL OSR exit #%u (%s, %s) from %s, with operands = %s, and record = %s",
exitID, toCString(exit.m_codeOrigin).data(),
