[wasm] Introduce special bytecodes for asm.js division/remainder instead of relying on module state.

src/wasm/asm-wasm-builder.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 // Required to get M_E etc. in MSVC.
 #if defined(_WIN32)
 #define _USE_MATH_DEFINES
 #endif
@@ skipping 1365 matching lines @@
         return MatchMul(expr);
       default:
         return kNone;
     }
   }
 
 // Work around Mul + Div being defined in PPC assembler.
 #ifdef Mul
 #undef Mul
 #endif
-#ifdef Div
-#undef Div
-#endif
 
 #define NON_SIGNED_BINOP(op)      \
   static WasmOpcode opcodes[] = { \
     kExprI32##op,                 \
     kExprI32##op,                 \
     kExprF32##op,                 \
     kExprF64##op                  \
   }
 
 #define SIGNED_BINOP(op)          \
@@ skipping 58 matching lines @@
       RECURSE(Visit(expr->right()));
 
       if (expr->op() == Token::COMMA) {
         current_function_builder_->Emit(kExprEnd);
       }
 
       switch (expr->op()) {
         BINOP_CASE(Token::ADD, Add, NON_SIGNED_BINOP, true);
         BINOP_CASE(Token::SUB, Sub, NON_SIGNED_BINOP, true);
         BINOP_CASE(Token::MUL, Mul, NON_SIGNED_BINOP, true);
-        BINOP_CASE(Token::DIV, Div, SIGNED_BINOP, false);
         BINOP_CASE(Token::BIT_OR, Ior, NON_SIGNED_INT_BINOP, true);
         BINOP_CASE(Token::BIT_AND, And, NON_SIGNED_INT_BINOP, true);
         BINOP_CASE(Token::BIT_XOR, Xor, NON_SIGNED_INT_BINOP, true);
         BINOP_CASE(Token::SHL, Shl, NON_SIGNED_INT_BINOP, true);
         BINOP_CASE(Token::SAR, ShrS, NON_SIGNED_INT_BINOP, true);
         BINOP_CASE(Token::SHR, ShrU, NON_SIGNED_INT_BINOP, true);
+        case Token::DIV: {
+          static WasmOpcode opcodes[] = {kExprI32AsmjsDivS, kExprI32AsmjsDivU,
+                                         kExprF32Div, kExprF64Div};
+          int type = TypeIndexOf(expr->left(), expr->right(), false);
+          current_function_builder_->Emit(opcodes[type]);
+          break;
+        }
         case Token::MOD: {
           TypeIndex type = TypeIndexOf(expr->left(), expr->right(), false);
           if (type == kInt32) {
-            current_function_builder_->Emit(kExprI32RemS);
+            current_function_builder_->Emit(kExprI32AsmjsRemS);
           } else if (type == kUint32) {
-            current_function_builder_->Emit(kExprI32RemU);
+            current_function_builder_->Emit(kExprI32AsmjsRemU);
           } else if (type == kFloat64) {
             current_function_builder_->Emit(kExprF64Mod);
             return;
           } else {
             UNREACHABLE();
           }
           break;
         }
         case Token::COMMA: {
           break;
@@ skipping 211 matching lines @@
 // that zone in constructor may be thrown away once wasm module is written.
 WasmModuleIndex* AsmWasmBuilder::Run() {
   AsmWasmBuilderImpl impl(isolate_, zone_, literal_, foreign_, typer_);
   impl.Compile();
   WasmModuleWriter* writer = impl.builder_->Build(zone_);
   return writer->WriteTo(zone_);
 }
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8