From 4e9ee1dc80ce353640c1e2134249a1f93da9229a Mon Sep 17 00:00:00 2001 From: Copilot <198982749+Copilot@users.noreply.github.com> Date: Tue, 26 Aug 2025 18:58:44 +0000 Subject: Fix Metal 8-bit vector type names: emit char/uchar instead of int8_t/uint8_t (#8223) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The Metal backend was generating incorrect type names for 8-bit vector types, causing compilation failures when targeting Metal. According to the Metal specification, 8-bit vector types should be named `charN` and `ucharN` (e.g., `char2`, `uchar3`) rather than `int8_tN` and `uint8_tN`. ## Problem When compiling Slang code with 8-bit vector types for Metal, the compiler would emit: ```metal uint8_t2 _S8 = uint8_t2(uint8_t(0U), uint8_t(16U)); int8_t3 _S9 = int8_t3(int8_t(0), int8_t(16), int8_t(48)); ``` But the Metal compiler expects: ```metal uchar2 _S8 = uchar2(uint8_t(0U), uint8_t(16U)); char3 _S9 = char3(int8_t(0), int8_t(16), int8_t(48)); ``` This caused errors like: ``` error: unknown type name 'uint8_t2'; did you mean 'uint8_t'? ``` ## Solution Modified `MetalSourceEmitter::emitSimpleTypeImpl()` to emit the correct Metal-specific type names for 8-bit types: - `kIROp_Int8Type` now emits `char` instead of `int8_t` - `kIROp_UInt8Type` now emits `uchar` instead of `uint8_t` This change only affects the Metal backend and ensures that vector types like `int8_t2`, `uint8_t3`, etc. are correctly emitted as `char2`, `uchar3`, etc. ## Testing - Added a new test case `tests/metal/8bit-vector-types.slang` to verify the fix - Re-enabled the previously disabled Metal test in `tests/hlsl-intrinsic/countbits8.slang` - Updated `tests/metal/byte-address-buffer.slang` to expect the correct type names - Verified that existing Metal tests continue to pass Fixes #8211. --- 💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more [Copilot coding agent tips](https://gh.io/copilot-coding-agent-tips) in the docs. --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: bmillsNV <163073245+bmillsNV@users.noreply.github.com> --- source/slang/slang-emit-metal.cpp | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'source/slang') diff --git a/source/slang/slang-emit-metal.cpp b/source/slang/slang-emit-metal.cpp index 9858e51a1..b19e85044 100644 --- a/source/slang/slang-emit-metal.cpp +++ b/source/slang/slang-emit-metal.cpp @@ -1071,9 +1071,7 @@ void MetalSourceEmitter::emitSimpleTypeImpl(IRType* type) { case kIROp_VoidType: case kIROp_BoolType: - case kIROp_Int8Type: case kIROp_IntType: - case kIROp_UInt8Type: case kIROp_UIntType: case kIROp_FloatType: case kIROp_HalfType: @@ -1081,6 +1079,12 @@ void MetalSourceEmitter::emitSimpleTypeImpl(IRType* type) m_writer->emit(getDefaultBuiltinTypeName(type->getOp())); return; } + case kIROp_Int8Type: + m_writer->emit("char"); + return; + case kIROp_UInt8Type: + m_writer->emit("uchar"); + return; case kIROp_Int64Type: m_writer->emit("long"); return; -- cgit v1.2.3