From 643c13668d8325d40bffea657be31ae3d19c5cea Mon Sep 17 00:00:00 2001
From: "Herman S." <429230+has207@users.noreply.github.com>
Date: Sat, 18 Oct 2025 11:33:02 +0900
Subject: [PATCH] [CPU] Correctly zero extend instead of sign extending

When performing unsigned multiplication on Linux/GCC,
the code incorrectly cast constant.i64 (which is a signed int64_t)
to unsigned __int128. This caused sign extension when
the value should be treated as unsigned.
---
 src/xenia/cpu/hir/value.cc | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/xenia/cpu/hir/value.cc b/src/xenia/cpu/hir/value.cc
index 06c41cd8a..c1538e705 100644
--- a/src/xenia/cpu/hir/value.cc
+++ b/src/xenia/cpu/hir/value.cc
@@ -413,8 +413,10 @@ void Value::MulHi(Value* other, bool is_unsigned) {
 #else
       if (is_unsigned) {
         constant.i64 = static_cast<uint64_t>(
-            (static_cast<unsigned __int128>(constant.i64) *
-             static_cast<unsigned __int128>(other->constant.i64)) >>
+            (static_cast<unsigned __int128>(
+                 static_cast<uint64_t>(constant.i64)) *
+             static_cast<unsigned __int128>(
+                 static_cast<uint64_t>(other->constant.i64))) >>
             64);
       } else {
         constant.i64 = static_cast<uint64_t>(