x64: Fix 64 bit shift code generation.

Mike Pall · Mike Pall · commit 03a7ebca4f68 · 2020-09-25T22:49:23.000+02:00
Reported by Philipp Kutin.
Fix contributed by Peter Cawley.
diff --git a/src/lj_asm_x86.h b/src/lj_asm_x86.h
@@ -2300,7 +2300,7 @@ static void asm_bitshift(ASMState *as, IRIns *ir, x86Shift xs, x86Op xv)
     dest = ra_dest(as, ir, rset_exclude(RSET_GPR, RID_ECX));
     if (dest == RID_ECX) {
       dest = ra_scratch(as, rset_exclude(RSET_GPR, RID_ECX));
-      emit_rr(as, XO_MOV, RID_ECX, dest);
+      emit_rr(as, XO_MOV, REX_64IR(ir, RID_ECX), dest);
     }
     right = irr->r;
     if (ra_noreg(right))

Original file line number	Diff line number	Diff line change
`@@ -2300,7 +2300,7 @@ static void asm_bitshift(ASMState as, IRIns ir, x86Shift xs, x86Op xv)`
`2300`	`2300`	`dest = ra_dest(as, ir, rset_exclude(RSET_GPR, RID_ECX));`
`2301`	`2301`	`if (dest == RID_ECX) {`
`2302`	`2302`	`dest = ra_scratch(as, rset_exclude(RSET_GPR, RID_ECX));`
`2303`		`- emit_rr(as, XO_MOV, RID_ECX, dest);`
	`2303`	`+ emit_rr(as, XO_MOV, REX_64IR(ir, RID_ECX), dest);`
`2304`	`2304`	`}`
`2305`	`2305`	`right = irr->r;`
`2306`	`2306`	`if (ra_noreg(right))`