Make x87 stack tracking more robust and avoid spilling

src/ia32/lithium-gap-resolver-ia32.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 347 matching lines @@
         XMMRegister dst = cgen_->ToDoubleRegister(destination);
         __ movaps(dst, src);
       } else {
         ASSERT(destination->IsDoubleStackSlot());
         Operand dst = cgen_->ToOperand(destination);
         __ movdbl(dst, src);
       }
     } else {
       // load from the register onto the stack, store in destination, which must
       // be a double stack slot in the non-SSE2 case.
-      ASSERT(destination->IsDoubleStackSlot());
-      Operand dst = cgen_->ToOperand(destination);
       X87Register src = cgen_->ToX87Register(source);
-      cgen_->X87Mov(dst, src);
+      if (destination->IsDoubleStackSlot()) {
+        Operand dst = cgen_->ToOperand(destination);
+        cgen_->X87Mov(dst, src);
+      } else {
+        ASSERT(destination->IsDoubleRegister());
+        X87Register dst = cgen_->ToX87Register(destination);
+        cgen_->X87Mov(dst, src);
+      }
     }
   } else if (source->IsDoubleStackSlot()) {
     if (CpuFeatures::IsSupported(SSE2)) {
       CpuFeatureScope scope(cgen_->masm(), SSE2);
       ASSERT(destination->IsDoubleRegister() ||
              destination->IsDoubleStackSlot());
       Operand src = cgen_->ToOperand(source);
       if (destination->IsDoubleRegister()) {
         XMMRegister dst = cgen_->ToDoubleRegister(destination);
         __ movdbl(dst, src);
@@ skipping 158 matching lines @@
   } else if (destination->IsRegister()) {
     source_uses_[destination->index()] = CountSourceUses(destination);
   }
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32