8080650: Enable stubs to use frame pointers correctly

Summary: Change MacroAssembler::verified_entry() to set up RBP correctly when generating stub code.
Reviewed-by: kvn

src/cpu/x86/vm/macroAssembler_x86.cpp

@@ -6143,7 +6143,9 @@ void MacroAssembler::verified_entry(int framesize, int stack_bang_size, bool fp_
     // Save caller's stack pointer into RBP if the frame pointer is preserved.
     if (PreserveFramePointer) {
       movptr(rbp, rsp);
-      addptr(rbp, framesize + wordSize);
+      if (framesize > 0) {
+        addptr(rbp, framesize);
+      }
     }
   }
 

src/cpu/x86/vm/x86_32.ad

@@ -566,7 +566,11 @@ void MachPrologNode::format(PhaseRegAlloc* ra_, outputStream* st) const {
     st->print("MOV    [ESP + #%d], EBP\t# Save EBP",framesize);
     if (PreserveFramePointer) {
       st->print("\n\t");
-      st->print("MOV    EBP, [ESP + #%d]\t# Save the caller's SP into EBP", (framesize + wordSize));
+      st->print("MOV    EBP, ESP\t# Save the caller's SP into EBP");
+      if (framesize > 0) {
+        st->print("\n\t");
+        st->print("ADD    EBP, #%d", framesize);
+      }
     }
   }
 

src/cpu/x86/vm/x86_64.ad

@@ -863,7 +863,11 @@ void MachPrologNode::format(PhaseRegAlloc* ra_, outputStream* st) const {
     st->print("movq    [rsp + #%d], rbp\t# Save rbp",framesize);    
     if (PreserveFramePointer) {
       st->print("\n\t");
-      st->print("movq    rbp, [rsp + #%d]\t# Save the caller's SP into rbp", (framesize + wordSize));
+      st->print("movq    rbp, rsp\t# Save the caller's SP into rbp");
+      if (framesize > 0) {
+        st->print("\n\t");
+        st->print("addq    rbp, #%d", framesize);
+      }      
     }
   }