[x86] Fix register constraints for multiply-high.

src/compiler/x64/instruction-selector-x64.cc

Index: src/compiler/x64/instruction-selector-x64.cc
diff --git a/src/compiler/x64/instruction-selector-x64.cc b/src/compiler/x64/instruction-selector-x64.cc
index 230e000c4721bcf7f1a08ed6dc5a3b5c3f2900fc..03240c2b282a8f91e141f1b3d36547417f986059 100644
--- a/src/compiler/x64/instruction-selector-x64.cc
+++ b/src/compiler/x64/instruction-selector-x64.cc
@@ -560,10 +560,9 @@ void InstructionSelector::VisitInt64Mul(Node* node) {
 void InstructionSelector::VisitInt32MulHigh(Node* node) {
   X64OperandGenerator g(this);
   InstructionOperand* temps[] = {g.TempRegister(rax)};
-  size_t temp_count = arraysize(temps);
   Emit(kX64ImulHigh32, g.DefineAsFixed(node, rdx),
-       g.UseFixed(node->InputAt(0), rax), g.UseRegister(node->InputAt(1)),
-       temp_count, temps);
+       g.UseFixed(node->InputAt(0), rax), g.UseUniqueRegister(node->InputAt(1)),
+       arraysize(temps), temps);
 }