[turbofan] Fix typo in IA-32 code generator.

TEST=benchmarks/octane/zlib
TBR=jarin@chromium.org

Review URL: https://codereview.chromium.org/633373002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24461 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/compiler/ia32/code-generator-ia32.cc

@@ -990,7 +990,7 @@ void CodeGenerator::AssembleSwap(InstructionOperand* source,
     __ movaps(xmm0, src);
     __ movaps(src, dst);
     __ movaps(dst, xmm0);
-  } else if (source->IsDoubleRegister() && source->IsDoubleStackSlot()) {
+  } else if (source->IsDoubleRegister() && destination->IsDoubleStackSlot()) {
     // XMM register-memory swap.  We rely on having xmm0
     // available as a fixed scratch register.
     XMMRegister reg = g.ToDoubleRegister(source);