From d9dc86b640301116fba81483fd1a50edfe270085 Mon Sep 17 00:00:00 2001
From: Nicolas Brunie <82109999+nibrunieAtSi5@users.noreply.github.com>
Date: Thu, 21 Dec 2023 10:36:16 -0800
Subject: [PATCH] UB in negate in mulh/mulhsu

Ensuring No negation on -2^63(int64_t) is performed during mulh/mulhsu

Signed-off-by: Nicolas Brunie <82109999+nibrunieAtSi5@users.noreply.github.com>
---
 riscv/arith.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/riscv/arith.h b/riscv/arith.h
index c60fcbea5f..7e471b2cb6 100644
--- a/riscv/arith.h
+++ b/riscv/arith.h
@@ -32,14 +32,14 @@ inline uint64_t mulhu(uint64_t a, uint64_t b)
 inline int64_t mulh(int64_t a, int64_t b)
 {
   int negate = (a < 0) != (b < 0);
-  uint64_t res = mulhu(a < 0 ? -a : a, b < 0 ? -b : b);
+  uint64_t res = mulhu(a < 0 ? -(uint64_t)a : a, b < 0 ? -(uint64_t)b : b);
   return negate ? ~res + ((uint64_t)a * (uint64_t)b == 0) : res;
 }
 
 inline int64_t mulhsu(int64_t a, uint64_t b)
 {
   int negate = a < 0;
-  uint64_t res = mulhu(a < 0 ? -a : a, b);
+  uint64_t res = mulhu(a < 0 ? -(uint64_t)a : a, b);
   return negate ? ~res + (a * b == 0) : res;
 }