Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Fix clipping bug in M68000 ADD/CMP/SUB instructions #178

Merged
merged 1 commit into from
May 11, 2021
Merged

Fix clipping bug in M68000 ADD/CMP/SUB instructions #178

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 3 additions & 3 deletions higan/component/processor/m68k/algorithms.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,5 +1,5 @@
template<uint Size, bool extend> auto M68K::ADD(uint32 source, uint32 target) -> uint32 {
auto result = (uint64)source + target;
auto result = (uint64)clip<Size>(source) + clip<Size>(target);
if(extend) result += r.x;

r.c = sign<Size>(result >> 1) < 0;
Expand Down Expand Up @@ -61,7 +61,7 @@ template<uint Size> auto M68K::ASR(uint32 result, uint shift) -> uint32 {
}

template<uint Size> auto M68K::CMP(uint32 source, uint32 target) -> uint32 {
auto result = (uint64)target - source;
auto result = (uint64)clip<Size>(target) - clip<Size>(source);

r.c = sign<Size>(result >> 1) < 0;
r.v = sign<Size>((target ^ source) & (target ^ result)) < 0;
Expand Down Expand Up @@ -192,7 +192,7 @@ template<uint Size> auto M68K::ROXR(uint32 result, uint shift) -> uint32 {
}

template<uint Size, bool extend> auto M68K::SUB(uint32 source, uint32 target) -> uint32 {
auto result = (uint64)target - source;
auto result = (uint64)clip<Size>(target) - clip<Size>(source);
if(extend) result -= r.x;

r.c = sign<Size>(result >> 1) < 0;
Expand Down