From a4ae39973ff2e77b233c467fbd0e49cc55d72f56 Mon Sep 17 00:00:00 2001
From: gameblabla <gameblabla@users.noreply.github.com>
Date: Sun, 22 Aug 2021 22:31:18 +0000
Subject: [PATCH] psxinterpreter: Merge DIV interpreter fix from libretro's
fork (#193)
Fix comes from here :
https://github.com/libretro/pcsx_rearmed/pull/530
Co-authored-by: Ember Cold <embercold@outlook.com>
---
libpcsxcore/psxinterpreter.c | 29 +++++++++++++++++++++--------
1 file changed, 21 insertions(+), 8 deletions(-)
diff --git a/libpcsxcore/psxinterpreter.c b/libpcsxcore/psxinterpreter.c
index fa454e1a..e59f93d8 100644
--- a/libpcsxcore/psxinterpreter.c
+++ b/libpcsxcore/psxinterpreter.c
@@ -501,14 +501,27 @@ void psxSLTU() { if (!_Rd_) return; _rRd_ = _u32(_rRs_) < _u32(_rRt_); } // Rd
* Format: OP rs, rt *
*********************************************************/
void psxDIV() {
- if (_i32(_rRt_) != 0) {
- _i32(_rLo_) = _i32(_rRs_) / _i32(_rRt_);
- _i32(_rHi_) = _i32(_rRs_) % _i32(_rRt_);
- }
- else {
- _i32(_rLo_) = _i32(_rRs_) >= 0 ? 0xffffffff : 1;
- _i32(_rHi_) = _i32(_rRs_);
- }
+ if (!_i32(_rRt_)) {
+ _i32(_rHi_) = _i32(_rRs_);
+ if (_i32(_rRs_) & 0x80000000) {
+ _i32(_rLo_) = 1;
+ } else {
+ _i32(_rLo_) = 0xFFFFFFFF;
+ }
+/*
+ * Notaz said that this was "not needed" for ARM platforms and could slow it down so let's disable for ARM.
+ * This fixes a crash issue that can happen when running Amidog's CPU test.
+ * (It still stays stuck to a black screen but at least it doesn't crash anymore)
+ */
+#if !defined(__arm__) && !defined(__aarch64__)
+ } else if (_i32(_rRs_) == 0x80000000 && _i32(_rRt_) == 0xFFFFFFFF) {
+ _i32(_rLo_) = 0x80000000;
+ _i32(_rHi_) = 0;
+#endif
+ } else {
+ _i32(_rLo_) = _i32(_rRs_) / _i32(_rRt_);
+ _i32(_rHi_) = _i32(_rRs_) % _i32(_rRt_);
+ }
}
void psxDIVU() {
--
2.39.5