[Mlir-commits] [mlir] ba6d7a0 - [mlir][AMDGPU] Add gfx941 to buffer atomics emulation

[Krzysztof Drewniak]

Author: Krzysztof Drewniak
Date: 2023-09-13T16:07:07Z
New Revision: ba6d7a0f25f335a3106d2949dda18a15ac188792

URL: https://github.com/llvm/llvm-project/commit/ba6d7a0f25f335a3106d2949dda18a15ac188792
DIFF: https://github.com/llvm/llvm-project/commit/ba6d7a0f25f335a3106d2949dda18a15ac188792.diff

LOG: [mlir][AMDGPU] Add gfx941 to buffer atomics emulation

Reviewed By: fmorac

Differential Revision: https://reviews.llvm.org/D152299

Added: 
    

Modified: 
    mlir/lib/Dialect/AMDGPU/Transforms/EmulateAtomics.cpp

Removed: 
    


################################################################################
diff  --git a/mlir/lib/Dialect/AMDGPU/Transforms/EmulateAtomics.cpp b/mlir/lib/Dialect/AMDGPU/Transforms/EmulateAtomics.cpp
index 8147de5ba5c3ba7..f89e2537897e804 100644
--- a/mlir/lib/Dialect/AMDGPU/Transforms/EmulateAtomics.cpp
+++ b/mlir/lib/Dialect/AMDGPU/Transforms/EmulateAtomics.cpp
@@ -152,7 +152,7 @@ void mlir::amdgpu::populateAmdgpuEmulateAtomicsPatterns(
   }
   // gfx9 has no to a very limited support for floating-point min and max.
   if (chipset.majorVersion == 9) {
-    if (chipset.minorVersion >= 0x0a) {
+    if (chipset.minorVersion >= 0x0a && chipset.minorVersion != 0x41) {
       // gfx90a supports f64 max (and min, but we don't have a min wrapper right
       // now) but all other types need to be emulated.
       target.addDynamicallyLegalOp<RawBufferAtomicFmaxOp>(
@@ -162,10 +162,18 @@ void mlir::amdgpu::populateAmdgpuEmulateAtomicsPatterns(
     } else {
       target.addIllegalOp<RawBufferAtomicFmaxOp>();
     }
+    if (chipset.minorVersion == 0x41) {
+      // gfx941 requires non-CAS atomics to be implemented with CAS loops.
+      // The workaround here mirrors HIP and OpenMP.
+      target.addIllegalOp<RawBufferAtomicFaddOp, RawBufferAtomicFmaxOp,
+                          RawBufferAtomicSmaxOp, RawBufferAtomicUminOp>();
+    }
   }
   patterns.add<
       RawBufferAtomicByCasPattern<RawBufferAtomicFaddOp, arith::AddFOp>,
-      RawBufferAtomicByCasPattern<RawBufferAtomicFmaxOp, arith::MaximumFOp>>(
+      RawBufferAtomicByCasPattern<RawBufferAtomicFmaxOp, arith::MaximumFOp>,
+      RawBufferAtomicByCasPattern<RawBufferAtomicSmaxOp, arith::MaxSIOp>,
+      RawBufferAtomicByCasPattern<RawBufferAtomicUminOp, arith::MinUIOp>>(
       patterns.getContext());
 }