Skip to content

fix(gs): decode sceGsSetDefDBuff trailing args via EABI registers, not o32 stack offsets #186

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

Draft
smmathews wants to merge 1 commit into
base: main
Choose a base branch
from
Draft

fix(gs): decode sceGsSetDefDBuff trailing args via EABI registers, not o32 stack offsets #186

Show file tree
Hide file tree
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
7 changes: 4 additions & 3 deletions ps2xRuntime/src/lib/Kernel/Stubs/GS.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1122,9 +1122,10 @@ namespace ps2_stubs
uint32_t psm = getRegU32(ctx, 5);
uint32_t w = getRegU32(ctx, 6);
uint32_t h = getRegU32(ctx, 7);
const uint32_t ztest = readStackU32(rdram, ctx, 16);
const uint32_t zpsm = readStackU32(rdram, ctx, 20);
const uint32_t clear = readStackU32(rdram, ctx, 24);
const GsTrailingArgs3 trailing = decodeGsTrailingArgs3(rdram, ctx);
const uint32_t ztest = trailing.arg0;
const uint32_t zpsm = trailing.arg1;
const uint32_t clear = trailing.arg2;
(void)clear;

if (w == 0u)
Expand Down
43 changes: 43 additions & 0 deletions ps2xTest/src/ps2_gs_tests.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -594,6 +594,49 @@ void register_ps2_gs_tests()
"sceGsSwapDBuffDc should honor a clear packet seeded from register-based trailing args");
});

tc.Run("sceGsSetDefDBuff decodes trailing args from the recompiler register ABI", [](TestCase &t)
{
PS2Runtime runtime;
t.IsTrue(runtime.memory().initialize(), "runtime memory initialize should succeed");

std::vector<uint8_t> rdram(PS2_RAM_SIZE, 0u);
constexpr uint32_t kEnvAddr = 0x9000u;
constexpr uint32_t kStackAddr = 0xC00u;
constexpr uint32_t kZbuf1ValOffset = 0x60u + 0x10u;
constexpr uint32_t kTest1ValOffset = 0x60u + 0x70u;

R5900Context ctx{};
setRegU32(ctx, 4, kEnvAddr);
setRegU32(ctx, 5, 0u);
setRegU32(ctx, 6, 640u);
setRegU32(ctx, 7, 448u);
setRegU32(ctx, 8, 2u); // ztest
setRegU32(ctx, 9, 1u); // zpsm
setRegU32(ctx, 10, 1u); // clear
setRegU32(ctx, 29, kStackAddr);

const uint32_t kStackZtest = 1u;
std::memcpy(rdram.data() + kStackAddr + 16u, &kStackZtest, sizeof(kStackZtest));
const uint32_t kStackZpsm = 0xEu;
std::memcpy(rdram.data() + kStackAddr + 20u, &kStackZpsm, sizeof(kStackZpsm));
const uint32_t kStackClear = 1u;
std::memcpy(rdram.data() + kStackAddr + 24u, &kStackClear, sizeof(kStackClear));

std::memset(rdram.data() + kEnvAddr, 0xCD, 0x330u);

ps2_stubs::sceGsSetDefDBuff(rdram.data(), &ctx, &runtime);

uint64_t zbuf1 = 0u;
std::memcpy(&zbuf1, rdram.data() + kEnvAddr + kZbuf1ValOffset, sizeof(zbuf1));
uint64_t test1 = 0u;
std::memcpy(&test1, rdram.data() + kEnvAddr + kTest1ValOffset, sizeof(test1));

t.Equals((zbuf1 >> 24) & 0xFull, 1ull,
"sceGsSetDefDBuff should seed ZBUF PSM from the register-passed zpsm argument, not caller stack bytes");
t.Equals((test1 >> 17) & 0x3ull, 2ull,
"sceGsSetDefDBuff should seed TEST from the register-passed ztest argument, not caller stack bytes");
});

tc.Run("clearFramebufferContext clears the requested context even if another context is active", [](TestCase &t)
{
std::vector<uint8_t> vram(PS2_GS_VRAM_SIZE, 0u);
Expand Down