Add volatile XLOADs.

2 files changed, 6 insertions, 2 deletions

diff --git a/src/lj_ir.h b/src/lj_ir.h
index d3104017..68901325 100644
--- a/src/lj_ir.h
+++ b/src/lj_ir.h
@@ -206,7 +206,8 @@ IRFLDEF(FLENUM)
 
 /* XLOAD mode, stored in op2. */
 #define IRXLOAD_READONLY        1       /* Load from read-only data. */
-#define IRXLOAD_UNALIGNED       2       /* Unaligned load. */
+#define IRXLOAD_VOLATILE        2       /* Load from volatile data. */
+#define IRXLOAD_UNALIGNED       4       /* Unaligned load. */
 
 /* CONV mode, stored in op2. */
 #define IRCONV_SRCMASK          0x001f  /* Source IRType. */
diff --git a/src/lj_opt_mem.c b/src/lj_opt_mem.c
index 9c22362b..cad85bb7 100644
--- a/src/lj_opt_mem.c
+++ b/src/lj_opt_mem.c
@@ -669,6 +669,8 @@ TRef LJ_FASTCALL lj_opt_fwd_xload(jit_State *J)
 
   if ((fins->op2 & IRXLOAD_READONLY))
     goto cselim;
+  if ((fins->op2 & IRXLOAD_VOLATILE))
+    goto doemit;
 
   /* Search for conflicting stores. */
   ref = J->chain[IR_XSTORE];
@@ -721,7 +723,8 @@ cselim:
     xr = IR(xref);
     goto retry;  /* Retry with the reassociated reference. */
   }
-  return lj_ir_emit(J);
+doemit:
+  return EMITFOLD;
 }
 
 /* XSTORE elimination. */