--- a/hotspot/src/cpu/x86/vm/c1_MacroAssembler_x86.cpp Wed Feb 15 16:29:40 2012 -0800
+++ b/hotspot/src/cpu/x86/vm/c1_MacroAssembler_x86.cpp Wed Feb 15 21:37:49 2012 -0800
@@ -381,6 +381,16 @@
void C1_MacroAssembler::verified_entry() {
+ if (C1Breakpoint || VerifyFPU || !UseStackBanging) {
+ // Verified Entry first instruction should be 5 bytes long for correct
+ // patching by patch_verified_entry().
+ //
+ // C1Breakpoint and VerifyFPU have one byte first instruction.
+ // Also first instruction will be one byte "push(rbp)" if stack banging
+ // code is not generated (see build_frame() above).
+ // For all these cases generate long instruction first.
+ fat_nop();
+ }
if (C1Breakpoint)int3();
// build frame
verify_FPU(0, "method_entry");