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[wasm] Remove dead handling of RUNTIME_ENTRY relocations.

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The RelocInfo::RUNTIME_ENTRY relocation mode is only used for deopt
points in JavaScript code and should never appear in WebAssembly code.

R=titzer@chromium.org

Change-Id: Ied1d61e2b1eb886565d13448442dd6a6ed35d3f0
Reviewed-on: https://chromium-review.googlesource.com/1070197
Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53340}
This commit is contained in:
Michael Starzinger 2018-05-24 12:49:13 +02:00 committed by Commit Bot
parent 815f9461f7
commit 8ac37bc392
3 changed files with 35 additions and 22 deletions
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39
src/wasm/wasm-code-manager.cc
View File

@ -255,6 +255,39 @@ void WasmCode::LogCode(Isolate* isolate) const {
}
}
void WasmCode::Validate() const {
#ifdef DEBUG
// We expect certain relocation info modes to never appear in {WasmCode}
// objects or to be restricted to a small set of valid values. Hence the
// iteration below does not use a mask, but visits all relocation data.
for (RelocIterator it(instructions(), reloc_info(), constant_pool());
!it.done(); it.next()) {
RelocInfo::Mode mode = it.rinfo()->rmode();
switch (mode) {
case RelocInfo::CODE_TARGET:
// TODO(mstarzinger): Validate that we go through a trampoline.
case RelocInfo::WASM_CODE_TABLE_ENTRY:
case RelocInfo::WASM_GLOBAL_HANDLE:
case RelocInfo::WASM_CALL:
case RelocInfo::JS_TO_WASM_CALL:
case RelocInfo::EXTERNAL_REFERENCE:
case RelocInfo::COMMENT:
case RelocInfo::CONST_POOL:
case RelocInfo::VENEER_POOL:
// These are OK to appear.
break;
case RelocInfo::EMBEDDED_OBJECT: {
HeapObject* o = it.rinfo()->target_object();
DCHECK(o->IsUndefined(o->GetIsolate()) || o->IsNull(o->GetIsolate()));
break;
}
default:
FATAL("Unexpected mode: %d", mode);
}
}
#endif
}
void WasmCode::Print(Isolate* isolate) const {
OFStream os(stdout);
Disassemble(nullptr, isolate, os);
@ -550,7 +583,6 @@ WasmCode* NativeModule::AddCode(
// TODO(mtrofin): this is a copy and paste from Code::CopyFrom.
int mode_mask = RelocInfo::kCodeTargetMask |
RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY) |
RelocInfo::kApplyMask;
// Needed to find target_object and runtime_entry on X64
@ -570,10 +602,6 @@ WasmCode* NativeModule::AddCode(
Code* code = Code::cast(*p);
it.rinfo()->set_target_address(GetLocalAddressFor(handle(code)),
SKIP_WRITE_BARRIER, SKIP_ICACHE_FLUSH);
} else if (RelocInfo::IsRuntimeEntry(mode)) {
Address p = it.rinfo()->target_runtime_entry(origin);
it.rinfo()->set_target_runtime_entry(p, SKIP_WRITE_BARRIER,
SKIP_ICACHE_FLUSH);
} else {
intptr_t delta = ret->instructions().start() - desc.buffer;
it.rinfo()->apply(delta);
@ -583,6 +611,7 @@ WasmCode* NativeModule::AddCode(
// made while iterating over the RelocInfo above.
Assembler::FlushICache(ret->instructions().start(),
ret->instructions().size());
ret->Validate();
return ret;
}

1
src/wasm/wasm-code-manager.h
View File

@ -135,6 +135,7 @@ class V8_EXPORT_PRIVATE WasmCode final {
// trap_handler_index.
void RegisterTrapHandlerData();
void Validate() const;
void Print(Isolate* isolate) const;
void Disassemble(const char* name, Isolate* isolate, std::ostream& os,
Address current_pc = kNullAddress) const;

17
src/wasm/wasm-serialization.cc
View File

@ -316,7 +316,6 @@ void NativeModuleSerializer::WriteCode(const WasmCode* code, Writer* writer) {
// Relocate the code.
int mask = RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
RelocInfo::ModeMask(RelocInfo::WASM_CALL) |
RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY) |
RelocInfo::ModeMask(RelocInfo::EXTERNAL_REFERENCE);
RelocIterator orig_iter(code->instructions(), code->reloc_info(),
code->constant_pool(), mask);
@ -337,13 +336,6 @@ void NativeModuleSerializer::WriteCode(const WasmCode* code, Writer* writer) {
uint32_t tag = wasm_targets_lookup_[orig_target];
SetWasmCalleeTag(iter.rinfo(), tag);
} break;
case RelocInfo::RUNTIME_ENTRY: {
Address orig_target = orig_iter.rinfo()->target_address();
auto ref_iter = reference_table_lookup_.find(orig_target);
DCHECK(ref_iter != reference_table_lookup_.end());
uint32_t tag = ref_iter->second;
SetWasmCalleeTag(iter.rinfo(), tag);
} break;
case RelocInfo::EXTERNAL_REFERENCE: {
Address orig_target = orig_iter.rinfo()->target_external_reference();
auto ref_iter = reference_table_lookup_.find(orig_target);
@ -491,7 +483,6 @@ bool NativeModuleDeserializer::ReadCode(uint32_t fn_index, Reader* reader) {
// now relocate the code
int mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
RelocInfo::ModeMask(RelocInfo::CODE_TARGET) |
RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY) |
RelocInfo::ModeMask(RelocInfo::EXTERNAL_REFERENCE) |
RelocInfo::ModeMask(RelocInfo::WASM_CODE_TABLE_ENTRY);
for (RelocIterator iter(ret->instructions(), ret->reloc_info(),
@ -512,14 +503,6 @@ bool NativeModuleDeserializer::ReadCode(uint32_t fn_index, Reader* reader) {
SKIP_ICACHE_FLUSH);
break;
}
case RelocInfo::RUNTIME_ENTRY: {
uint32_t tag = GetWasmCalleeTag(iter.rinfo());
Address address =
isolate_->heap()->external_reference_table()->address(tag);
iter.rinfo()->set_target_runtime_entry(address, SKIP_WRITE_BARRIER,
SKIP_ICACHE_FLUSH);
break;
}
case RelocInfo::EXTERNAL_REFERENCE: {
uint32_t tag = GetWasmCalleeTag(iter.rinfo());
Address address =