commit 82c80de14da66b80474b298ae99cbff37cdf9b53
author Udayan Banerji <udayan.banerji@intel.com> Fri Mar 29 13:32:10 2013 -0700
committer Elliott Hughes <enh@google.com> Mon Apr 01 16:09:04 2013 -0700
tree 25eb810cd3bc5c3070814da57537880d3e5d9596
parent 442724597a3db9387c964a652fda6e125413ee7e

[x86] Terminate trace if SGET/SPUT have unresolved fields in codegen

The interpreter doesn't allow SGET/SPUT bytecodes in a trace till the field
is resolved. However, exhaustTrace can pick up bytecodes beyond the trace
sent by the interpreter. Terminate the loop formation if this is seen.

Signed-off-by: Udayan Banerji <udayan.banerji@intel.com>

(cherry picked from commit 4eb6d969de37f9b82aaa4089490900f620e50f46)

Change-Id: If5480640375a5152748e74e00be200d80f313b31

vm/compiler/codegen/x86/LowerGetPut.cpp

diff --git a/vm/compiler/codegen/x86/LowerGetPut.cpp b/vm/compiler/codegen/x86/LowerGetPut.cpp
index c87b174..be519b1 100644
--- a/vm/compiler/codegen/x86/LowerGetPut.cpp
+++ b/vm/compiler/codegen/x86/LowerGetPut.cpp
@@ -668,7 +668,17 @@
     void *fieldPtr = (void*)
         (currentMethod->clazz->pDvmDex->pResFields[tmp]);
 #endif
-    assert(fieldPtr != NULL);
+
+    /* Usually, fieldPtr should not be null. The interpreter should resolve
+     * it before we come here, or not allow this opcode in a trace. However,
+     * we can be in a loop trace and this opcode might have been picked up
+     * by exhaustTrace. Sending a -1 here will terminate the loop formation
+     * and fall back to normal trace, which will not have this opcode.
+     */
+    if (!fieldPtr) {
+        return -1;
+    }
+
     move_imm_to_reg(OpndSize_32, (int)fieldPtr, PhysicalReg_EAX, true);
     if(flag == SGET) {
         move_mem_to_reg(OpndSize_32, offStaticField_value, PhysicalReg_EAX, true, 7, false); //access field