Commit 8d0be491 authored by Julien Pages's avatar Julien Pages
Browse files

Bug 1783956 - Add a new MIR node MWasmTrapIfNull. r=rhunt 

This simplifies the control-flow when compiling ref.as_non_null
with the ion backend.

Differential Revision: https://phabricator.services.mozilla.com/D173202
parent d445a907

js/src/jit/CodeGenerator.cpp

+11 −0
Original line number Diff line number Diff line
@@ -16616,6 +16616,17 @@ void CodeGenerator::visitWasmTrap(LWasmTrap* lir) { 
  masm.wasmTrap(mir->trap(), mir->bytecodeOffset());

}









void CodeGenerator::visitWasmTrapIfNull(LWasmTrapIfNull* lir) {









  MOZ_ASSERT(gen->compilingWasm());









  const MWasmTrapIfNull* mir = lir->mir();









  Label nonNull;









  Register input = ToRegister(lir->object());

















  masm.branchTestPtr(Assembler::NonZero, input, input, &nonNull);









  masm.wasmTrap(mir->trap(), mir->bytecodeOffset());









  masm.bind(&nonNull);









}

















void CodeGenerator::visitWasmGcObjectIsSubtypeOf(









    LWasmGcObjectIsSubtypeOf* ins) {









  MOZ_ASSERT(gen->compilingWasm());

























js/src/jit/LIROps.yaml



+5
−0






























Original line number
Diff line number
Diff line







@@ -297,6 +297,11 @@







- name: WasmTrap









  mir_op: true



















- name: WasmTrapIfNull









  operands:









    object: WordSized









  mir_op: true



















- name: WasmGcObjectIsSubtypeOf









  mir_op: true









  operands:
































js/src/jit/Lowering.cpp



+5
−0






























Original line number
Diff line number
Diff line







@@ -3354,6 +3354,11 @@ void LIRGenerator::visitWasmTrap(MWasmTrap* ins) {







  add(new (alloc()) LWasmTrap, ins);









}



















void LIRGenerator::visitWasmTrapIfNull(MWasmTrapIfNull* ins) {









  auto* lir = new (alloc()) LWasmTrapIfNull(useRegister(ins->value()));









  add(lir, ins);









}



















void LIRGenerator::visitWasmReinterpret(MWasmReinterpret* ins) {









  if (ins->type() == MIRType::Int64) {









    defineInt64(new (alloc())
































js/src/jit/MIROps.yaml



+11
−0






























Original line number
Diff line number
Diff line







@@ -1028,6 +1028,17 @@







- name: WasmTrap









  gen_boilerplate: false



















# Trap if the given value is null









- name: WasmTrapIfNull









  operands:









    value: RefOrNull









  arguments:









    trap: wasm::Trap









    bytecodeOffset: wasm::BytecodeOffset









  guard: true









  type_policy: none









  result_type: None



















- name: LexicalCheck









  gen_boilerplate: false










































js/src/wasm/WasmIonCompile.cpp



+3
−22






























Original line number
Diff line number
Diff line







@@ -848,29 +848,10 @@ class FunctionCompiler {







      return true;









    }



















    MBasicBlock* joinBlock = nullptr;









    if (!newBlock(curBlock_, &joinBlock)) {









      return false;









    }



















    MBasicBlock* trapBlock = nullptr;









    if (!newBlock(curBlock_, &trapBlock)) {









      return false;









    }









    auto* ins = MWasmTrap::New(alloc(), wasm::Trap::NullPointerDereference,









                               bytecodeOffset());









    trapBlock->end(ins);









    auto* ins = MWasmTrapIfNull::New(









        alloc(), value, wasm::Trap::NullPointerDereference, bytecodeOffset());



















    MDefinition* check = compareIsNull(value, JSOp::Ne);









    if (!check) {









      return false;









    }









    MTest* test = MTest::New(alloc(), check, joinBlock, trapBlock);









    if (!test) {









      return false;









    }









    curBlock_->end(test);









    curBlock_ = joinBlock;









    curBlock_->add(ins);









    return true;









  }