Never call MacroAssembler::Allocate() with incorrect size.

src/x87/lithium-codegen-x87.cc

Index: src/x87/lithium-codegen-x87.cc
diff --git a/src/x87/lithium-codegen-x87.cc b/src/x87/lithium-codegen-x87.cc
index 00bbe5e72bab8245367fd7619bdd6c09b94b1414..6241edf3756d0d669d9f553d71924597160c69f1 100644
--- a/src/x87/lithium-codegen-x87.cc
+++ b/src/x87/lithium-codegen-x87.cc
@@ -5749,7 +5749,8 @@ void LCodeGen::DoAllocate(LAllocate* instr) {
 
   if (instr->size()->IsConstantOperand()) {
     int32_t size = ToInteger32(LConstantOperand::cast(instr->size()));
-    if (size <= Page::kMaxRegularHeapObjectSize) {
+    if (static_cast<uint32_t>(size) <=
+        static_cast<uint32_t>(Page::kMaxRegularHeapObjectSize)) {
       __ Allocate(size, result, temp, no_reg, deferred->entry(), flags);
     } else {
       __ jmp(deferred->entry());