FFI: Fix recording of bool call result check on x86/x64.

src/lj_asm_x86.h

@@ -1815,7 +1815,7 @@ static void asm_intarith(ASMState *as, IRIns *ir, x86Arith xa)
   int32_t k = 0;
   if (as->flagmcp == as->mcp) {  /* Drop test r,r instruction. */
     as->flagmcp = NULL;
-    as->mcp += (LJ_64 && *as->mcp != XI_TEST) ? 3 : 2;
+    as->mcp += (LJ_64 && *as->mcp < XI_TESTb) ? 3 : 2;
   }
   right = IR(rref)->r;
   if (ra_hasreg(right)) {
@@ -2151,7 +2151,7 @@ static void asm_comp(ASMState *as, IRIns *ir, uint32_t cc)
 	asm_guardcc(as, cc);
 	if (usetest && left != RID_MRM) {
 	  /* Use test r,r instead of cmp r,0. */
-	  emit_rr(as, XO_TEST, r64 + left, left);
+	  emit_rr(as, irt_isu8(ir->t) ? XO_TESTb : XO_TEST, r64 + left, left);
 	  if (irl+1 == ir)  /* Referencing previous ins? */
 	    as->flagmcp = as->mcp;  /* Set flag to drop test r,r if possible. */
 	} else {

src/lj_crecord.c

@@ -1140,7 +1140,12 @@ static int crec_call(jit_State *J, RecordFFData *rd, GCcdata *cd)
 	tr = TREF_NIL;
       } else {
 	crec_snap_caller(J);
+#if LJ_TARGET_X86ORX64
+	/* Note: only the x86/x64 backend supports U8 and only for EQ(tr, 0). */
+	lj_ir_set(J, IRTG(IR_NE, IRT_U8), tr, lj_ir_kint(J, 0));
+#else
 	lj_ir_set(J, IRTGI(IR_NE), tr, lj_ir_kint(J, 0));
+#endif
 	J->postproc = LJ_POST_FIXGUARDSNAP;
 	tr = TREF_TRUE;
       }

src/lj_target_x86.h

@@ -205,6 +205,7 @@ typedef enum {
   XI_ARITHi =	0x81,
   XI_ARITHi8 =	0x83,
   XI_PUSHi8 =	0x6a,
+  XI_TESTb =	0x84,
   XI_TEST =	0x85,
   XI_MOVmi =	0xc7,
   XI_GROUP5 =	0xff,
@@ -244,6 +245,7 @@ typedef enum {
   XO_IMULi =	XO_(69),
   XO_IMULi8 =	XO_(6b),
   XO_CMP =	XO_(3b),
+  XO_TESTb =	XO_(84),
   XO_TEST =	XO_(85),
   XO_GROUP3b =	XO_(f6),
   XO_GROUP3 =	XO_(f7),