AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

[stringrefs] Implement string.const

Browse Source 
Current implementation doesn't cache the result, however.

Bug: v8:12868
Change-Id: Idd5eb7bbb49d018fec82a80bffb5288c0b6ee0f8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695377
Commit-Queue: Andy Wingo <wingo@igalia.com>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81006}
This commit is contained in:
Andy Wingo 2022-06-08 17:39:39 +02:00 committed by V8 LUCI CQ
parent 62159ea316
commit c842874cb5
16 changed files with 171 additions and 44 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
src/builtins/wasm.tq
View File

@ -42,6 +42,7 @@ extern runtime WasmStringNewWtf8(
Context, WasmInstanceObject, Smi, Number, Number): String;
extern runtime WasmStringNewWtf16(
Context, WasmInstanceObject, Smi, Number, Number): String;
extern runtime WasmStringConst(Context, WasmInstanceObject, Smi): String;
}
namespace unsafe {
@ -795,4 +796,9 @@ builtin WasmStringNewWtf16(
LoadContextFromInstance(instance), instance, SmiFromUint32(memory),
WasmUint32ToNumber(offset), WasmUint32ToNumber(size));
}
builtin WasmStringConst(index: uint32): String {
const instance = LoadInstanceFromFrame();
tail runtime::WasmStringConst(
LoadContextFromInstance(instance), instance, SmiFromUint32(index));
}
}

5
src/compiler/wasm-compiler.cc
View File

@ -5752,6 +5752,11 @@ Node* WasmGraphBuilder::StringNewWtf16(uint32_t memory, Node* offset,
gasm_->Uint32Constant(memory), offset, size);
}
Node* WasmGraphBuilder::StringConst(uint32_t index) {
return gasm_->CallBuiltin(Builtin::kWasmStringConst, Operator::kNoDeopt,
gasm_->Uint32Constant(index));
}
// 1 bit V8 Smi tag, 31 bits V8 Smi shift, 1 bit i31ref high-bit truncation.
constexpr int kI31To32BitSmiShift = 33;

1
src/compiler/wasm-compiler.h
View File

@ -540,6 +540,7 @@ class WasmGraphBuilder {
Node** no_match_control, Node** no_match_effect);
Node* StringNewWtf8(uint32_t memory, Node* offset, Node* size);
Node* StringNewWtf16(uint32_t memory, Node* offset, Node* size);
Node* StringConst(uint32_t index);
Node* IsNull(Node* object);
Node* TypeGuard(Node* value, wasm::ValueType type);

27
src/runtime/runtime-wasm.cc
View File

@ -886,5 +886,32 @@ RUNTIME_FUNCTION(Runtime_WasmStringNewWtf16) {
return *result;
}
// Returns the new string if the operation succeeds. Otherwise traps.
RUNTIME_FUNCTION(Runtime_WasmStringConst) {
ClearThreadInWasmScope flag_scope(isolate);
DCHECK_EQ(2, args.length());
HandleScope scope(isolate);
Handle<WasmInstanceObject> instance = args.at<WasmInstanceObject>(0);
static_assert(
base::IsInRange(wasm::kV8MaxWasmStringLiterals, 0, Smi::kMaxValue));
uint32_t index = args.positive_smi_value_at(1);
DCHECK_LT(index, instance->module()->stringref_literals.size());
const wasm::WasmStringRefLiteral& literal =
instance->module()->stringref_literals[index];
const base::Vector<const uint8_t> module_bytes =
instance->module_object().native_module()->wire_bytes();
const base::Vector<const uint8_t> string_bytes =
module_bytes.SubVector(literal.source.offset(),
literal.source.offset() + literal.source.length());
// TODO(12868): Override any exception with an uncatchable-by-wasm trap?
// TODO(12868): No need to re-validate WTF-8. Also, result should be cached.
Handle<String> result;
ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
isolate, result, isolate->factory()->NewStringFromWtf8(string_bytes));
return *result;
}
} // namespace internal
} // namespace v8

3
src/runtime/runtime.h
View File

@ -613,7 +613,8 @@ namespace internal {
F(WasmSyncStackLimit, 0, 1) \
F(WasmCreateResumePromise, 2, 1) \
F(WasmStringNewWtf8, 4, 1) \
F(WasmStringNewWtf16, 4, 1)
F(WasmStringNewWtf16, 4, 1) \
F(WasmStringConst, 2, 1)
#define FOR_EACH_INTRINSIC_WASM_TEST(F, I) \
F(DeserializeWasmModule, 2, 1) \

17
src/wasm/baseline/liftoff-compiler.cc
View File

@ -6063,7 +6063,22 @@ class LiftoffCompiler {
void StringConst(FullDecoder* decoder,
const StringConstImmediate<validate>& imm, Value* result) {
UNIMPLEMENTED();
LiftoffRegList pinned;
LiftoffRegister index_reg =
pinned.set(__ GetUnusedRegister(kGpReg, pinned));
__ LoadConstant(index_reg, WasmValue(static_cast<int32_t>(imm.index)));
LiftoffAssembler::VarState index_var(kI32, index_reg, 0);
CallRuntimeStub(WasmCode::kWasmStringConst,
MakeSig::Returns(kRef).Params(kI32),
{
index_var,
},
decoder->position());
RegisterDebugSideTableEntry(decoder, DebugSideTableBuilder::kDidSpill);
LiftoffRegister result_reg(kReturnRegister0);
__ PushRegister(kRef, result_reg);
}
void StringMeasureUtf8(FullDecoder* decoder, const Value& str,

44
src/wasm/function-body-decoder-impl.h
View File

@ -966,27 +966,28 @@ struct ControlBase : public PcForErrors<validate> {
F(NextInstruction, WasmOpcode) \
F(Forward, const Value& from, Value* to)
#define INTERFACE_CONSTANT_FUNCTIONS(F) \
F(I32Const, Value* result, int32_t value) \
F(I64Const, Value* result, int64_t value) \
F(F32Const, Value* result, float value) \
F(F64Const, Value* result, double value) \
F(S128Const, Simd128Immediate<validate>& imm, Value* result) \
F(BinOp, WasmOpcode opcode, const Value& lhs, const Value& rhs, \
Value* result) \
F(RefNull, ValueType type, Value* result) \
F(RefFunc, uint32_t function_index, Value* result) \
F(GlobalGet, Value* result, const GlobalIndexImmediate<validate>& imm) \
F(StructNewWithRtt, const StructIndexImmediate<validate>& imm, \
const Value& rtt, const Value args[], Value* result) \
F(StructNewDefault, const StructIndexImmediate<validate>& imm, \
const Value& rtt, Value* result) \
F(ArrayInit, const ArrayIndexImmediate<validate>& imm, \
const base::Vector<Value>& elements, const Value& rtt, Value* result) \
F(ArrayInitFromSegment, const ArrayIndexImmediate<validate>& array_imm, \
const IndexImmediate<validate>& data_segment, const Value& offset, \
const Value& length, const Value& rtt, Value* result) \
F(RttCanon, uint32_t type_index, Value* result) \
#define INTERFACE_CONSTANT_FUNCTIONS(F) /* force 80 columns */ \
F(I32Const, Value* result, int32_t value) \
F(I64Const, Value* result, int64_t value) \
F(F32Const, Value* result, float value) \
F(F64Const, Value* result, double value) \
F(S128Const, Simd128Immediate<validate>& imm, Value* result) \
F(BinOp, WasmOpcode opcode, const Value& lhs, const Value& rhs, \
Value* result) \
F(RefNull, ValueType type, Value* result) \
F(RefFunc, uint32_t function_index, Value* result) \
F(GlobalGet, Value* result, const GlobalIndexImmediate<validate>& imm) \
F(StructNewWithRtt, const StructIndexImmediate<validate>& imm, \
const Value& rtt, const Value args[], Value* result) \
F(StructNewDefault, const StructIndexImmediate<validate>& imm, \
const Value& rtt, Value* result) \
F(ArrayInit, const ArrayIndexImmediate<validate>& imm, \
const base::Vector<Value>& elements, const Value& rtt, Value* result) \
F(ArrayInitFromSegment, const ArrayIndexImmediate<validate>& array_imm, \
const IndexImmediate<validate>& data_segment, const Value& offset, \
const Value& length, const Value& rtt, Value* result) \
F(RttCanon, uint32_t type_index, Value* result) \
F(StringConst, const StringConstImmediate<validate>& imm, Value* result) \
F(DoReturn, uint32_t drop_values)
#define INTERFACE_NON_CONSTANT_FUNCTIONS(F) /* force 80 columns */ \
@ -1135,7 +1136,6 @@ struct ControlBase : public PcForErrors<validate> {
const Value& offset, const Value& size, Value* result) \
F(StringNewWtf16, const MemoryIndexImmediate<validate>& imm, \
const Value& offset, const Value& size, Value* result) \
F(StringConst, const StringConstImmediate<validate>& imm, Value* result) \
F(StringMeasureUtf8, const Value& str, Value* result) \
F(StringMeasureWtf8, const Value& str, Value* result) \
F(StringMeasureWtf16, const Value& str, Value* result) \

2
src/wasm/graph-builder-interface.cc
View File

@ -1408,7 +1408,7 @@ class WasmGraphBuildingInterface {
void StringConst(FullDecoder* decoder,
const StringConstImmediate<validate>& imm, Value* result) {
UNIMPLEMENTED();
result->node = builder_->StringConst(imm.index);
}
void StringMeasureUtf8(FullDecoder* decoder, const Value& str,

20
src/wasm/init-expr-interface.cc
View File

@ -132,6 +132,26 @@ void InitExprInterface::StructNewWithRtt(
ValueType::Ref(HeapType(imm.index), kNonNullable));
}
void InitExprInterface::StringConst(FullDecoder* decoder,
const StringConstImmediate<validate>& imm,
Value* result) {
if (!generate_value()) return;
static_assert(base::IsInRange(kV8MaxWasmStringLiterals, 0, Smi::kMaxValue));
DCHECK_LT(imm.index, module_->stringref_literals.size());
const wasm::WasmStringRefLiteral& literal =
module_->stringref_literals[imm.index];
const base::Vector<const uint8_t> module_bytes =
instance_->module_object().native_module()->wire_bytes();
const base::Vector<const uint8_t> string_bytes =
module_bytes.SubVector(literal.source.offset(),
literal.source.offset() + literal.source.length());
Handle<String> string =
isolate_->factory()->NewStringFromWtf8(string_bytes).ToHandleChecked();
result->runtime_value = WasmValue(string, kWasmStringRef);
}
namespace {
WasmValue DefaultValueForType(ValueType type, Isolate* isolate) {
switch (type.kind()) {

3
src/wasm/wasm-code-manager.h
View File

@ -124,7 +124,8 @@ struct WasmModule;
V(WasmOnStackReplace) \
V(WasmSuspend) \
V(WasmStringNewWtf8) \
V(WasmStringNewWtf16)
V(WasmStringNewWtf16) \
V(WasmStringConst)
// Sorted, disjoint and non-overlapping memory regions. A region is of the
// form [start, end). So there's no [start, end), [end, other_end),

2
src/wasm/wasm-init-expr.cc
View File

@ -47,6 +47,8 @@ ValueType WasmInitExpr::type(const WasmModule* module,
return ValueType::Ref(immediate().index, kNonNullable);
case kRttCanon:
return ValueType::Rtt(immediate().heap_type);
case kStringConst:
return ValueType::Ref(HeapType::kString, kNonNullable);
}
}

9
src/wasm/wasm-init-expr.h
View File

@ -43,6 +43,7 @@ class WasmInitExpr : public ZoneObject {
kArrayInit,
kArrayInitStatic,
kRttCanon,
kStringConst,
};
union Immediate {
@ -147,6 +148,13 @@ class WasmInitExpr : public ZoneObject {
return expr;
}
static WasmInitExpr StringConst(uint32_t index) {
WasmInitExpr expr;
expr.kind_ = kStringConst;
expr.immediate_.index = index;
return expr;
}
Immediate immediate() const { return immediate_; }
Operator kind() const { return kind_; }
const ZoneVector<WasmInitExpr>* operands() const { return operands_; }
@ -159,6 +167,7 @@ class WasmInitExpr : public ZoneObject {
case kGlobalGet:
case kRefFuncConst:
case kRttCanon:
case kStringConst:
return immediate().index == other.immediate().index;
case kI32Const:
return immediate().i32_const == other.immediate().i32_const;

5
src/wasm/wasm-module-builder.cc
View File

@ -577,6 +577,11 @@ void WriteInitializerExpressionWithEnd(ZoneBuffer* buffer,
buffer->write_u8(static_cast<uint8_t>(kExprRttCanon));
buffer->write_i32v(static_cast<int32_t>(init.immediate().index));
break;
case WasmInitExpr::kStringConst:
buffer->write_u8(kGCPrefix);
buffer->write_u8(static_cast<uint8_t>(kExprStringConst));
buffer->write_u32v(init.immediate().index);
break;
}
}

8
test/fuzzer/wasm-fuzzer-common.cc
View File

@ -416,6 +416,11 @@ class InitExprInterface {
result->init_expr = WasmInitExpr::RttCanon(type_index);
}
void StringConst(FullDecoder* decoder,
const StringConstImmediate<validate>& imm, Value* result) {
result->init_expr = WasmInitExpr::StringConst(imm.index);
}
void DoReturn(FullDecoder* decoder, uint32_t /*drop_values*/) {
// End decoding on "end".
decoder->set_end(decoder->pc() + 1);
@ -493,6 +498,9 @@ void AppendInitExpr(std::ostream& os, const WasmInitExpr& expr) {
case WasmInitExpr::kRttCanon:
os << "RttCanon(" << expr.immediate().index;
break;
case WasmInitExpr::kStringConst:
os << "StringConst(" << expr.immediate().index;
break;
}
if (append_operands) {

51
test/mjsunit/wasm/stringrefs-exec.js
View File

@ -7,6 +7,7 @@
d8.file.execute("test/mjsunit/wasm/wasm-module-builder.js");
let kSig_w_ii = makeSig([kWasmI32, kWasmI32], [kWasmStringRef]);
let kSig_w_v = makeSig([], [kWasmStringRef]);
function encodeWtf8(str) {
// String iterator coalesces surrogate pairs.
@ -34,18 +35,20 @@ function encodeWtf8(str) {
return out;
}
let interestingStrings = ['',
'ascii',
'latin \xa9 1',
'two \ucccc byte',
'surrogate \ud800\udc000 pair',
'isolated \ud800 leading',
'isolated \udc00 trailing'];
function makeWtf8TestDataSegment() {
let data = []
let valid = {};
let invalid = {};
for (let str of ['',
'ascii',
'latin \xa9 1',
'two \ucccc byte',
'surrogate \ud800\udc000 pair',
'isolated \ud800 leading',
'isolated \udc00 trailing']) {
for (let str of interestingStrings) {
let bytes = encodeWtf8(str);
valid[str] = { offset: data.length, length: bytes.length };
for (let byte of bytes) {
@ -73,7 +76,7 @@ function makeWtf8TestDataSegment() {
builder.addDataSegment(0, data.data);
builder.addFunction("string_new_wtf8", kSig_w_ii)
.exportAs("string_new_wtf8")
.exportFunc()
.addBody([
kExprLocalGet, 0, kExprLocalGet, 1,
kGCPrefix, kExprStringNewWtf8, 0
@ -104,13 +107,7 @@ function makeWtf16TestDataSegment() {
let data = []
let valid = {};
for (let str of ['',
'ascii',
'latin \xa9 1',
'two \ucccc byte',
'surrogate \ud800\udc000 pair',
'isolated \ud800 leading',
'isolated \udc00 trailing']) {
for (let str of interestingStrings) {
valid[str] = { offset: data.length, length: str.length };
for (let byte of encodeWtf16LE(str)) {
data.push(byte);
@ -128,7 +125,7 @@ function makeWtf16TestDataSegment() {
builder.addDataSegment(0, data.data);
builder.addFunction("string_new_wtf16", kSig_w_ii)
.exportAs("string_new_wtf16")
.exportFunc()
.addBody([
kExprLocalGet, 0, kExprLocalGet, 1,
kGCPrefix, kExprStringNewWtf16, 0
@ -139,3 +136,25 @@ function makeWtf16TestDataSegment() {
assertEquals(str, instance.exports.string_new_wtf16(offset, length));
}
})();
(function TestStringConst() {
let builder = new WasmModuleBuilder();
for (let [index, str] of interestingStrings.entries()) {
builder.addLiteralStringRef(encodeWtf8(str));
builder.addFunction("string_const" + index, kSig_w_v)
.exportFunc()
.addBody([
kGCPrefix, kExprStringConst, index
]);
builder.addGlobal(kWasmStringRef, false, WasmInitExpr.StringConst(index))
.exportAs("global" + index);
}
let instance = builder.instantiate();
for (let [index, str] of interestingStrings.entries()) {
assertEquals(str, instance.exports["string_const" + index]());
assertEquals(str, instance.exports["global" + index].value);
}
})();

12
test/mjsunit/wasm/wasm-module-builder.js
View File

@ -1108,16 +1108,21 @@ class Binary {
break;
case kExprRttSub:
this.emit_init_expr_recursive(expr.parent);
this.emit_u8(kGcPrefix);
this.emit_u8(kGCPrefix);
this.emit_u8(kExprRttSub);
this.emit_u32v(expr.value);
break;
case kExprRttFreshSub:
this.emit_init_expr_recursive(expr.parent);
this.emit_u8(kGcPrefix);
this.emit_u8(kGCPrefix);
this.emit_u8(kExprRttFreshSub);
this.emit_u32v(expr.value);
break;
case kExprStringConst:
this.emit_u8(kGCPrefix);
this.emit_u8(kExprStringConst);
this.emit_u32v(expr.index);
break;
}
}
@ -1306,6 +1311,9 @@ class WasmInitExpr {
static RttFreshSub(type, parent) {
return {kind: kExprRttFreshSub, value: type, parent: parent};
}
static StringConst(index) {
return {kind: kExprStringConst, index};
}
static defaultFor(type) {
switch (type) {