ARM: Check that address given to __ RecordWrite is correct.

src/arm/macro-assembler-arm.cc

Index: src/arm/macro-assembler-arm.cc
===================================================================
--- src/arm/macro-assembler-arm.cc	(revision 9962)
+++ src/arm/macro-assembler-arm.cc	(working copy)
@@ -483,6 +483,15 @@
   // registers are cp.
   ASSERT(!address.is(cp) && !value.is(cp));
 
+  if (FLAG_debug_code) {

[Kevin Millikin (Chromium), 2011/11/11 11:28:37]

We don't use FLAG_debug_code in the macro assembler.  Use emit_debug_code so
that we can override the flag if we need to.

+    Label ok;
+    ldr(ip, MemOperand(address));
+    cmp(ip, value);
+    b(eq, &ok);

[Kevin Millikin (Chromium), 2011/11/11 11:32:23]

Also, while I think of it, is there a reason not to use

Check(eq, "Wrong address or value passed to RecordWrite")

?

+    stop("Wrong address or value passed to RecordWrite");
+    bind(&ok);
+  }
+
   Label done;
 
   if (smi_check == INLINE_SMI_CHECK) {