From 5dafadf749dcba0f33936a6fd6efe39b36042a34 Mon Sep 17 00:00:00 2001
From: Justus Klausecker <justus@klausecker.de>
Date: Fri, 11 Jul 2025 03:40:30 +0200
Subject: [PATCH] Sema: remove incorrect safety check for saturating left shift

---
 src/Sema.zig                    | 2 +-
 test/behavior/bit_shifting.zig  | 2 --
 test/behavior/x86_64/binary.zig | 2 --
 3 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/Sema.zig b/src/Sema.zig
index 92f6705e4ea3..0e48ef1746bd 100644
--- a/src/Sema.zig
+++ b/src/Sema.zig
@@ -14134,7 +14134,7 @@ fn zirShl(
     try sema.requireRuntimeBlock(block, src, runtime_src);
     if (block.wantSafety()) {
         const bit_count = scalar_ty.intInfo(zcu).bits;
-        if (!std.math.isPowerOfTwo(bit_count)) {
+        if (air_tag != .shl_sat and !std.math.isPowerOfTwo(bit_count)) {
             const bit_count_val = try pt.intValue(scalar_rhs_ty, bit_count);
             const ok = if (rhs_ty.zigTypeTag(zcu) == .vector) ok: {
                 const bit_count_inst = Air.internedToRef((try sema.splat(rhs_ty, bit_count_val)).toIntern());
diff --git a/test/behavior/bit_shifting.zig b/test/behavior/bit_shifting.zig
index 33742f21c40e..bf8ed261f821 100644
--- a/test/behavior/bit_shifting.zig
+++ b/test/behavior/bit_shifting.zig
@@ -169,8 +169,6 @@ test "Saturating Shift Left" {
 
     const S = struct {
         fn shlSat(x: anytype, y: std.math.Log2Int(@TypeOf(x))) @TypeOf(x) {
-            // workaround https://github.com/ziglang/zig/issues/23033
-            @setRuntimeSafety(false);
             return x <<| y;
         }
 
diff --git a/test/behavior/x86_64/binary.zig b/test/behavior/x86_64/binary.zig
index 99dd47155bbf..e90c4f1eb05a 100644
--- a/test/behavior/x86_64/binary.zig
+++ b/test/behavior/x86_64/binary.zig
@@ -5473,8 +5473,6 @@ inline fn shlSaturate(comptime Type: type, lhs: Type, rhs: Type) Type {
         // workaround https://github.com/ziglang/zig/issues/23139
         return lhs <<| @min(@abs(rhs), splat(ChangeScalar(Type, u64), imax(u64)));
     }
-    // workaround https://github.com/ziglang/zig/issues/23033
-    @setRuntimeSafety(false);
     return lhs <<| @abs(rhs);
 }
 test shlSaturate {