llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-hlsl Author: Finn Plummer (inbelic) <details> <summary>Changes</summary> `GroupMemoryBarrierWithGroupSync` is required to be marked as convergent so that it can't generate duplicate calls or be moved to identical control flow. Without it, we generate undefined behaviour during optimization. For instance: https://godbolt.org/z/9j3vsq1h3. Testing that the convergent attribute is added is sufficient. There already exists testing, [here](https://github.com/inbelic/llvm-project/blob/main/llvm/test/Transforms/SimplifyCFG/attr-convergent.ll), that it will not be moved as described in the above link. --- Full diff: https://github.com/llvm/llvm-project/pull/160175.diff 4 Files Affected: - (modified) clang/lib/Headers/hlsl/hlsl_alias_intrinsics.h (+1-1) - (modified) clang/test/CodeGenHLSL/builtins/GroupMemoryBarrierWithGroupSync.hlsl (+1-1) - (modified) llvm/include/llvm/IR/IntrinsicsDirectX.td (+2-1) - (modified) llvm/include/llvm/IR/IntrinsicsSPIRV.td (+2-1) ``````````diff diff --git a/clang/lib/Headers/hlsl/hlsl_alias_intrinsics.h b/clang/lib/Headers/hlsl/hlsl_alias_intrinsics.h index 21a9c30d9f445..cd1ffc8c23298 100644 --- a/clang/lib/Headers/hlsl/hlsl_alias_intrinsics.h +++ b/clang/lib/Headers/hlsl/hlsl_alias_intrinsics.h @@ -2805,7 +2805,7 @@ float4 radians(float4); /// call. _HLSL_BUILTIN_ALIAS(__builtin_hlsl_group_memory_barrier_with_group_sync) -void GroupMemoryBarrierWithGroupSync(void); +__attribute__((convergent)) void GroupMemoryBarrierWithGroupSync(void); } // namespace hlsl #endif //_HLSL_HLSL_ALIAS_INTRINSICS_H_ diff --git a/clang/test/CodeGenHLSL/builtins/GroupMemoryBarrierWithGroupSync.hlsl b/clang/test/CodeGenHLSL/builtins/GroupMemoryBarrierWithGroupSync.hlsl index 114230d38ba54..e709ed3616f0d 100644 --- a/clang/test/CodeGenHLSL/builtins/GroupMemoryBarrierWithGroupSync.hlsl +++ b/clang/test/CodeGenHLSL/builtins/GroupMemoryBarrierWithGroupSync.hlsl @@ -17,4 +17,4 @@ void test_GroupMemoryBarrierWithGroupSync() { // CHECK: declare void @llvm.[[TARGET]].group.memory.barrier.with.group.sync() #[[ATTRS:[0-9]+]] // CHECK-NOT: attributes #[[ATTRS]] = {{.+}}memory(none){{.+}} -// CHECK: attributes #[[ATTRS]] = { +// CHECK: attributes #[[ATTRS]] = {{.+}}convergent{{.+}} diff --git a/llvm/include/llvm/IR/IntrinsicsDirectX.td b/llvm/include/llvm/IR/IntrinsicsDirectX.td index 5d76c3f8df89d..e60e07801455f 100644 --- a/llvm/include/llvm/IR/IntrinsicsDirectX.td +++ b/llvm/include/llvm/IR/IntrinsicsDirectX.td @@ -160,5 +160,6 @@ def int_dx_firstbituhigh : DefaultAttrsIntrinsic<[LLVMScalarOrSameVectorWidth<0, def int_dx_firstbitshigh : DefaultAttrsIntrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i32_ty>], [llvm_anyint_ty], [IntrNoMem]>; def int_dx_firstbitlow : DefaultAttrsIntrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i32_ty>], [llvm_anyint_ty], [IntrNoMem]>; -def int_dx_group_memory_barrier_with_group_sync : DefaultAttrsIntrinsic<[], [], []>; +def int_dx_group_memory_barrier_with_group_sync + : DefaultAttrsIntrinsic<[], [], [IntrConvergent]>; } diff --git a/llvm/include/llvm/IR/IntrinsicsSPIRV.td b/llvm/include/llvm/IR/IntrinsicsSPIRV.td index bc026fa33c769..0b0c2b137e55b 100644 --- a/llvm/include/llvm/IR/IntrinsicsSPIRV.td +++ b/llvm/include/llvm/IR/IntrinsicsSPIRV.td @@ -127,7 +127,8 @@ def int_spv_rsqrt : DefaultAttrsIntrinsic<[LLVMMatchType<0>], [llvm_anyfloat_ty] : DefaultAttrsIntrinsic<[llvm_i32_ty], [], [IntrConvergent]>; def int_spv_sign : DefaultAttrsIntrinsic<[LLVMScalarOrSameVectorWidth<0, llvm_i32_ty>], [llvm_any_ty], [IntrNoMem]>; def int_spv_radians : DefaultAttrsIntrinsic<[LLVMMatchType<0>], [llvm_anyfloat_ty], [IntrNoMem]>; - def int_spv_group_memory_barrier_with_group_sync : DefaultAttrsIntrinsic<[], [], []>; + def int_spv_group_memory_barrier_with_group_sync + : DefaultAttrsIntrinsic<[], [], [IntrConvergent]>; def int_spv_discard : DefaultAttrsIntrinsic<[], [], []>; def int_spv_uclamp : DefaultAttrsIntrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, LLVMMatchType<0>, LLVMMatchType<0>], [IntrNoMem]>; def int_spv_sclamp : DefaultAttrsIntrinsic<[llvm_anyint_ty], [LLVMMatchType<0>, LLVMMatchType<0>, LLVMMatchType<0>], [IntrNoMem]>; `````````` </details> https://github.com/llvm/llvm-project/pull/160175 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
