From c7bbf29960c296f7b1b2193d771461c66333fae4 Mon Sep 17 00:00:00 2001
From: Wuerfel_21 <nunuu@gmx.net>
Date: Mon, 15 Jun 2026 00:10:33 +0200
Subject: [PATCH 1/2] Fix crash reported by evanh and add extra safety check

---
 backends/asm/optimize_ir.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/backends/asm/optimize_ir.c b/backends/asm/optimize_ir.c
index 4e726f6c8..77380a131 100644
--- a/backends/asm/optimize_ir.c
+++ b/backends/asm/optimize_ir.c
@@ -3710,7 +3710,7 @@ OptimizePeepholes(IRList *irl)
                     if (test_is_z && InstrUsesFlags(testir, FLAG_WC)) {
                         changeok = false;
                     } else if (InstrSetsAnyFlags(testir)) {
-                        changeok = sawir;
+                        changeok = sawir && (test_is_c || !FlagsUsedAt(testir->prev,FLAG_WZ));
                         lastir = testir;
                         break;
                     }
@@ -3726,7 +3726,7 @@ OptimizePeepholes(IRList *irl)
                         {
                             ReplaceZWithNC(testir);
                         }
-                        if (IsBranch(lastir)) {
+                        if (lastir != NULL && IsBranch(lastir)) {
                             ReplaceZWithNC(lastir);
                         }
                     }

From 297d024a36c379da6e06374bd550445de451c906 Mon Sep 17 00:00:00 2001
From: Wuerfel_21 <nunuu@gmx.net>
Date: Mon, 15 Jun 2026 00:28:47 +0200
Subject: [PATCH 2/2] fix test failure

---
 backends/asm/optimize_ir.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/backends/asm/optimize_ir.c b/backends/asm/optimize_ir.c
index 77380a131..73911ef65 100644
--- a/backends/asm/optimize_ir.c
+++ b/backends/asm/optimize_ir.c
@@ -3710,7 +3710,7 @@ OptimizePeepholes(IRList *irl)
                     if (test_is_z && InstrUsesFlags(testir, FLAG_WC)) {
                         changeok = false;
                     } else if (InstrSetsAnyFlags(testir)) {
-                        changeok = sawir && (test_is_c || !FlagsUsedAt(testir->prev,FLAG_WZ));
+                        changeok = sawir && (test_is_c || !FlagsUsedAt(testir,FLAG_WZ));
                         lastir = testir;
                         break;
                     }