From c631a90e22a861c2dfbfb244b30718837c9690b4 Mon Sep 17 00:00:00 2001
From: pagefault <>
Date: Wed, 19 Mar 2003 22:45:05 +0000
Subject: [PATCH] Signed saturation fix for gaussian interpolation (Thanks
 kode54)

---
 zsnes/src/cpu/dspproc.asm | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/zsnes/src/cpu/dspproc.asm b/zsnes/src/cpu/dspproc.asm
index 3b9affd8..cf910bb1 100644
--- a/zsnes/src/cpu/dspproc.asm
+++ b/zsnes/src/cpu/dspproc.asm
@@ -3549,6 +3549,16 @@ DSPInterpolate_4
     add ecx,edx
 
     sar ecx,11
+
+    cmp ecx, -32768
+    jge .sat1
+    mov ecx, -32768
+.sat1
+    cmp ecx, 32767
+    jle .sat2
+    mov ecx, 32767
+.sat2
+
     mov ax,cx
 	pop edi
 	ret
@@ -3610,13 +3620,13 @@ DSPInterpolate_4_mmx:
     packssdw mm0,[edx*4+PSampleBuf+edi+16]
     movq mm1,[DSPInterP+eax*8]
     pmaddwd mm0,mm1
-    movd eax, mm0
+    movq mm1, mm0
     psrlq mm0, 32
-    movd ebx, mm0
+    paddd mm0, mm1
+    psrad mm0, 11
+    packssdw mm0, mm0
+    movd eax, mm0
     emms
-    add eax,ebx
-    sar eax,11
-
     pop edi
     ret