ARM: Avoid duplicate vmla when merging vmul and vadd

src/arm/lithium-arm.cc

 // Copyright 2012 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"
 
 #include "src/lithium-allocator-inl.h"
 #include "src/arm/lithium-arm.h"
 #include "src/arm/lithium-codegen-arm.h"
 #include "src/hydrogen-osr.h"
@@ skipping 1482 matching lines @@
       }
       right_op = UseRegister(right);
     }
     LMulI* mul = new(zone()) LMulI(left_op, right_op);
     if (can_overflow || bailout_on_minus_zero) {
       AssignEnvironment(mul);
     }
     return DefineAsRegister(mul);
 
   } else if (instr->representation().IsDouble()) {
-    if (instr->UseCount() == 1 && (instr->uses().value()->IsAdd() ||
-                                   instr->uses().value()->IsSub())) {
+    if (instr->HasOneUse() && (instr->uses().value()->IsAdd() ||
+                               instr->uses().value()->IsSub())) {
       HBinaryOperation* use = HBinaryOperation::cast(instr->uses().value());
 
       if (use->IsAdd() && instr == use->left()) {
         // This mul is the lhs of an add. The add and mul will be folded into a
         // multiply-add in DoAdd.
         return NULL;
       }
       if (instr == use->right() && use->IsAdd() && !use->left()->IsMul()) {
         // This mul is the rhs of an add, where the lhs is not another mul.
         // The add and mul will be folded into a multiply-add in DoAdd.
@@ skipping 25 matching lines @@
 
     LOperand* left = UseRegisterAtStart(instr->left());
     LOperand* right = UseOrConstantAtStart(instr->right());
     LSubI* sub = new(zone()) LSubI(left, right);
     LInstruction* result = DefineAsRegister(sub);
     if (instr->CheckFlag(HValue::kCanOverflow)) {
       result = AssignEnvironment(result);
     }
     return result;
   } else if (instr->representation().IsDouble()) {
-    if (instr->right()->IsMul()) {
+    if (instr->right()->IsMul() && instr->right()->HasOneUse()) {
       return DoMultiplySub(instr->left(), HMul::cast(instr->right()));
     }
 
     return DoArithmeticD(Token::SUB, instr);
   } else {
     return DoArithmeticT(Token::SUB, instr);
   }
 }
 
 
@@ skipping 50 matching lines @@
   } else if (instr->representation().IsExternal()) {
     ASSERT(instr->left()->representation().IsExternal());
     ASSERT(instr->right()->representation().IsInteger32());
     ASSERT(!instr->CheckFlag(HValue::kCanOverflow));
     LOperand* left = UseRegisterAtStart(instr->left());
     LOperand* right = UseOrConstantAtStart(instr->right());
     LAddI* add = new(zone()) LAddI(left, right);
     LInstruction* result = DefineAsRegister(add);
     return result;
   } else if (instr->representation().IsDouble()) {
-    if (instr->left()->IsMul()) {
+    if (instr->left()->IsMul() && instr->left()->HasOneUse()) {
       return DoMultiplyAdd(HMul::cast(instr->left()), instr->right());
     }
 
-    if (instr->right()->IsMul()) {
-      ASSERT(!instr->left()->IsMul());
+    if (instr->right()->IsMul() && instr->right()->HasOneUse()) {
+      ASSERT(!instr->left()->IsMul() || !instr->left()->HasOneUse());
       return DoMultiplyAdd(HMul::cast(instr->right()), instr->left());
     }
 
     return DoArithmeticD(Token::ADD, instr);
   } else {
     return DoArithmeticT(Token::ADD, instr);
   }
 }
 
 
@@ skipping 952 matching lines @@
 LInstruction* LChunkBuilder::DoAllocateBlockContext(
     HAllocateBlockContext* instr) {
   LOperand* context = UseFixed(instr->context(), cp);
   LOperand* function = UseRegisterAtStart(instr->function());
   LAllocateBlockContext* result =
       new(zone()) LAllocateBlockContext(context, function);
   return MarkAsCall(DefineFixed(result, cp), instr);
 }
 
 } }  // namespace v8::internal