From: Florian Krohm <flo2030@eich-krohm.de>
Date: Thu, 14 Aug 2025 15:35:21 +0000 (+0000)
Subject: s390: Fix code generation for Iop_16Uto32(0x...:I16)
X-Git-Tag: VALGRIND_3_26_0~234
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=981db2c7289d4318a6c5a83eedf3607b27377d05;p=thirdparty%2Fvalgrind.git

s390: Fix code generation for Iop_16Uto32(0x...:I16)

Using LHI is wrong as it sign-extends. Use IILF instead.
This has been wrong since day #1. Found by iropt-test.
---

diff --git a/VEX/priv/host_s390_defs.c b/VEX/priv/host_s390_defs.c
index 1ee1696b3..c79aa11c0 100644
--- a/VEX/priv/host_s390_defs.c
+++ b/VEX/priv/host_s390_defs.c
@@ -9258,7 +9258,10 @@ s390_widen_emit(UChar *buf, const s390_insn *insn, UInt from_size,
 
       case 2:
          if (insn->size == 4) {  /* 16 --> 32 */
-            return s390_emit_LHI(buf, r1, value);
+            if (sign_extend)
+               return s390_emit_LHI(buf, r1, value);
+            else
+               return s390_emit_IILF(buf, r1, value);
          }
          if (insn->size == 8) {  /* 16 --> 64 */
             if (sign_extend)