[Mlir-commits] [mlir] [mlir][AMDGPU] Add PermlaneOp (PR #154345)

Tim Gymnich llvmlistbot at llvm.org
Thu Aug 21 01:56:31 PDT 2025


https://github.com/tgymnich updated https://github.com/llvm/llvm-project/pull/154345

>From a061dbaf32aaafe1ad302217382f9cfbb8cfac89 Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Mon, 18 Aug 2025 13:18:00 +0000
Subject: [PATCH 1/8] add AMDGPU PermlaneOp

---
 mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td |  29 ++++
 .../AMDGPUToROCDL/AMDGPUToROCDL.cpp           |  52 +++++-
 .../Conversion/AMDGPUToROCDL/permlane.mlir    | 153 ++++++++++++++++++
 mlir/test/Dialect/AMDGPU/ops.mlir             |  14 ++
 4 files changed, 247 insertions(+), 1 deletion(-)
 create mode 100644 mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir

diff --git a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
index 2c646934c11c2..17386a2888788 100644
--- a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
+++ b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
@@ -656,6 +656,35 @@ def AMDGPU_SwizzleBitModeOp : AMDGPU_Op<"swizzle_bitmode",
   }];
 }
 
+def AMDGPU_PermlanePerm : I32EnumAttr<"PermlanePerm",
+    "The possible permutations for a permlane operation",
+    [
+      I32EnumAttrCase<"swap_16",  0>,
+      I32EnumAttrCase<"swap_32",  1>,
+    ]> {
+  let genSpecializedAttr = 0;
+  let cppNamespace = "::mlir::amdgpu";
+}
+
+def AMDGPU_PermlanePermAttr : EnumAttr<AMDGPU_Dialect, AMDGPU_PermlanePerm,
+  "permlane_perm">;
+
+def AMDGPU_PermlaneOp : AMDGPU_Op<"permlane", [Pure, AllTypesMatch<["result", "src"]>]>,
+Arguments<(ins AnyIntegerOrFloatOr1DVector:$src, 
+                AMDGPU_PermlanePermAttr:$kind)> {
+  let summary = "AMDGPU permlane op";
+  let description = [{
+    High-level wrapper on `rocdl.permlane` variants.
+
+    Supports arbitrary int/float/vector types, which will be repacked to i32 and
+    one or more `rocdl.permlane` ops during lowering.
+  }];
+  let results = (outs AnyIntegerOrFloatOr1DVector:$result);
+  let assemblyFormat = [{
+    $src $kind attr-dict `:` type($result)
+  }];
+}
+
 def AMDGPU_LDSBarrierOp : AMDGPU_Op<"lds_barrier"> {
   let summary = "Barrier that includes a wait for LDS memory operations.";
   let description = [{
diff --git a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
index 64720bfe6cf50..4b0f8bcb40811 100644
--- a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
+++ b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
@@ -14,6 +14,7 @@
 #include "mlir/Dialect/AMDGPU/IR/AMDGPUDialect.h"
 #include "mlir/Dialect/AMDGPU/Utils/Chipset.h"
 #include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/Dialect/LLVMIR/LLVMTypes.h"
 #include "mlir/Dialect/LLVMIR/ROCDLDialect.h"
 #include "mlir/IR/BuiltinTypes.h"
 #include "mlir/IR/TypeUtilities.h"
@@ -1876,6 +1877,55 @@ struct AMDGPUSwizzleBitModeLowering
   }
 };
 
+struct AMDGPUPermlaneLowering : public ConvertOpToLLVMPattern<PermlaneOp> {
+  using ConvertOpToLLVMPattern::ConvertOpToLLVMPattern;
+
+  AMDGPUPermlaneLowering(const LLVMTypeConverter &converter, Chipset chipset)
+      : ConvertOpToLLVMPattern<PermlaneOp>(converter), chipset(chipset) {}
+  Chipset chipset;
+
+  LogicalResult
+  matchAndRewrite(PermlaneOp op, OpAdaptor adaptor,
+                  ConversionPatternRewriter &rewriter) const override {
+    Location loc = op.getLoc();
+    Type i32 = rewriter.getI32Type();
+    Value src = adaptor.getSrc();
+    auto kind = op.getKind();
+    auto fi = rewriter.getBoolAttr(false);
+    auto boundctrl = rewriter.getBoolAttr(false);
+
+    if (chipset < kGfx950)
+      return op->emitOpError("permlane_swap is only supported on gfx950+");
+
+    SmallVector<Value> decomposed =
+        LLVM::decomposeValue(rewriter, loc, src, i32);
+
+    SmallVector<Value> permuted;
+    for (Value v : decomposed) {
+      Value res;
+      Type i32pair = LLVM::LLVMStructType::getLiteral(
+          rewriter.getContext(), {v.getType(), v.getType()});
+      switch (kind) {
+      case PermlanePerm::swap_16:
+        res = ROCDL::Permlane16SwapOp::create(rewriter, loc, i32pair, v, v, fi,
+                                              boundctrl);
+        break;
+      case PermlanePerm::swap_32:
+        res = ROCDL::Permlane32SwapOp::create(rewriter, loc, i32pair, v, v, fi,
+                                              boundctrl);
+        break;
+      }
+
+      Value vdstNew = LLVM::ExtractValueOp::create(rewriter, loc, res, {0});
+      permuted.emplace_back(vdstNew);
+    }
+
+    Value result = LLVM::composeValue(rewriter, loc, permuted, src.getType());
+    rewriter.replaceOp(op, result);
+    return success();
+  }
+};
+
 struct ConvertAMDGPUToROCDLPass
     : public impl::ConvertAMDGPUToROCDLPassBase<ConvertAMDGPUToROCDLPass> {
   using Base::Base;
@@ -1944,6 +1994,6 @@ void mlir::populateAMDGPUToROCDLConversionPatterns(LLVMTypeConverter &converter,
            WMMAOpLowering, ExtPackedFp8OpLowering, ScaledExtPackedOpLowering,
            PackedScaledTruncOpLowering, PackedTrunc2xFp8OpLowering,
            PackedStochRoundFp8OpLowering, GatherToLDSOpLowering,
-           TransposeLoadOpLowering>(converter, chipset);
+           TransposeLoadOpLowering, AMDGPUPermlaneLowering>(converter, chipset);
   patterns.add<AMDGPUSwizzleBitModeLowering>(converter);
 }
diff --git a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
new file mode 100644
index 0000000000000..5b216e393043f
--- /dev/null
+++ b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
@@ -0,0 +1,153 @@
+// RUN: mlir-opt -convert-amdgpu-to-rocdl=chipset=gfx950 --canonicalize %s | FileCheck %s
+
+// CHECK-LABEL: func @test_permlane16_i32
+// CHECK-SAME: (%[[ARG0:.*]]: i32)
+func.func @test_permlane16_i32(%arg0 : i32) -> i32 {
+// CHECK:  %[[PERM:.*]] = rocdl.permlane16.swap %[[ARG0]], %[[ARG0]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  return %[[RES]] : i32
+  %0 = amdgpu.permlane %arg0 swap_16 : i32
+  return %0 : i32
+}
+
+// CHECK-LABEL: func @test_permlane32_i32
+// CHECK-SAME: (%[[ARG0:.*]]: i32)
+func.func @test_permlane32_i32(%arg0 : i32) -> i32 {
+// CHECK:  %[[PERM:.*]] = rocdl.permlane32.swap %[[ARG0]], %[[ARG0]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  return %[[RES]] : i32
+  %0 = amdgpu.permlane %arg0 swap_32 : i32
+  return %0 : i32
+}
+
+// CHECK-LABEL: func @test_permlane16_f32
+// CHECK-SAME: (%[[ARG0:.*]]: f32)
+func.func @test_permlane16_f32(%arg0 : f32) -> f32 {
+// CHECK:  %[[CAST:.*]] = llvm.bitcast %[[ARG0]] : f32 to i32
+// CHECK:  %[[PERM:.*]] = rocdl.permlane16.swap %[[CAST]], %[[CAST]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  %[[RES_CAST:.*]] = llvm.bitcast %[[RES]] : i32 to f32
+// CHECK:  return %[[RES_CAST]] : f32
+  %0 = amdgpu.permlane %arg0 swap_16 : f32
+  return %0 : f32
+}
+
+// CHECK-LABEL: func @test_permlane32_f32
+// CHECK-SAME: (%[[ARG0:.*]]: f32)
+func.func @test_permlane32_f32(%arg0 : f32) -> f32 {
+// CHECK:  %[[CAST:.*]] = llvm.bitcast %[[ARG0]] : f32 to i32
+// CHECK:  %[[PERM:.*]] = rocdl.permlane32.swap %[[CAST]], %[[CAST]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  %[[RES_CAST:.*]] = llvm.bitcast %[[RES]] : i32 to f32
+// CHECK:  return %[[RES_CAST]] : f32
+  %0 = amdgpu.permlane %arg0 swap_32 : f32
+  return %0 : f32
+}
+
+// CHECK-LABEL: func @test_permlane16_f16
+// CHECK-SAME: (%[[ARG0:.*]]: f16)
+func.func @test_permlane16_f16(%arg0 : f16) -> f16 {
+// CHECK:  %[[CAST:.*]] = llvm.bitcast %[[ARG0]] : f16 to i16
+// CHECK:  %[[ZEXT:.*]] = llvm.zext %[[CAST]] : i16 to i32
+// CHECK:  %[[PERM:.*]] = rocdl.permlane16.swap %[[ZEXT]], %[[ZEXT]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  %[[TRUNC:.*]] = llvm.trunc %[[RES]] : i32 to i16
+// CHECK:  %[[RES_CAST:.*]] = llvm.bitcast %[[TRUNC]] : i16 to f16
+// CHECK:  return %[[RES_CAST]] : f16
+  %0 = amdgpu.permlane %arg0 swap_16 : f16
+  return %0 : f16
+}
+
+// CHECK-LABEL: func @test_permlane32_f16
+// CHECK-SAME: (%[[ARG0:.*]]: f16)
+func.func @test_permlane32_f16(%arg0 : f16) -> f16 {
+// CHECK:  %[[CAST:.*]] = llvm.bitcast %[[ARG0]] : f16 to i16
+// CHECK:  %[[ZEXT:.*]] = llvm.zext %[[CAST]] : i16 to i32
+// CHECK:  %[[PERM:.*]] = rocdl.permlane32.swap %[[ZEXT]], %[[ZEXT]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  %[[TRUNC:.*]] = llvm.trunc %[[RES]] : i32 to i16
+// CHECK:  %[[RES_CAST:.*]] = llvm.bitcast %[[TRUNC]] : i16 to f16
+// CHECK:  return %[[RES_CAST]] : f16
+  %0 = amdgpu.permlane %arg0 swap_32 : f16
+  return %0 : f16
+}
+
+// CHECK-LABEL: func @test_permlane16_2xi32
+// CHECK-SAME: (%[[ARG0:.*]]: vector<2xi32>)
+func.func @test_permlane16_2xi32(%arg0 : vector<2xi32>) -> vector<2xi32> {
+// CHECK-DAG:  %[[POISON:.*]] = llvm.mlir.poison : vector<2xi32>
+// CHECK-DAG:  %[[C1:.*]] = llvm.mlir.constant(1 : i32) : i32
+// CHECK-DAG:  %[[C0:.*]] = llvm.mlir.constant(0 : i32) : i32
+// CHECK:      %[[ELEM0:.*]] = llvm.extractelement %[[ARG0]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[ELEM1:.*]] = llvm.extractelement %[[ARG0]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      %[[PERM0_TUPLE:.*]] = rocdl.permlane16.swap %[[ELEM0]], %[[ELEM0]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM0:.*]] = llvm.extractvalue %[[PERM0_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[PERM1_TUPLE:.*]] = rocdl.permlane16.swap %[[ELEM1]], %[[ELEM1]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM1:.*]] = llvm.extractvalue %[[PERM1_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[VEC_INSERT0:.*]] = llvm.insertelement %[[PERM0]], %[[POISON]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[VEC_INSERT1:.*]] = llvm.insertelement %[[PERM1]], %[[VEC_INSERT0]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      return %[[VEC_INSERT1]] : vector<2xi32>
+  %0 = amdgpu.permlane %arg0 swap_16 : vector<2xi32>
+  return %0 : vector<2xi32>
+}
+
+// CHECK-LABEL: func @test_permlane32_2xi32
+// CHECK-SAME: (%[[ARG0:.*]]: vector<2xi32>)
+func.func @test_permlane32_2xi32(%arg0 : vector<2xi32>) -> vector<2xi32> {
+// CHECK-DAG:  %[[POISON:.*]] = llvm.mlir.poison : vector<2xi32>
+// CHECK-DAG:  %[[C1:.*]] = llvm.mlir.constant(1 : i32) : i32
+// CHECK-DAG:  %[[C0:.*]] = llvm.mlir.constant(0 : i32) : i32
+// CHECK:      %[[ELEM0:.*]] = llvm.extractelement %[[ARG0]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[ELEM1:.*]] = llvm.extractelement %[[ARG0]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      %[[PERM0_TUPLE:.*]] = rocdl.permlane32.swap %[[ELEM0]], %[[ELEM0]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM0:.*]] = llvm.extractvalue %[[PERM0_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[PERM1_TUPLE:.*]] = rocdl.permlane32.swap %[[ELEM1]], %[[ELEM1]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM1:.*]] = llvm.extractvalue %[[PERM1_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[VEC_INSERT0:.*]] = llvm.insertelement %[[PERM0]], %[[POISON]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[VEC_INSERT1:.*]] = llvm.insertelement %[[PERM1]], %[[VEC_INSERT0]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      return %[[VEC_INSERT1]] : vector<2xi32>
+  %0 = amdgpu.permlane %arg0 swap_32 : vector<2xi32>
+  return %0 : vector<2xi32>
+}
+
+// CHECK-LABEL: func @test_permlane16_4xf16
+// CHECK-SAME: (%[[ARG0:.*]]: vector<4xf16>)
+func.func @test_permlane16_4xf16(%arg0 : vector<4xf16>) -> vector<4xf16> {
+// CHECK-DAG:  %[[POISON:.*]] = llvm.mlir.poison : vector<2xi32>
+// CHECK-DAG:  %[[C1:.*]] = llvm.mlir.constant(1 : i32) : i32
+// CHECK-DAG:  %[[C0:.*]] = llvm.mlir.constant(0 : i32) : i32
+// CHECK:      %[[CAST1:.*]] = llvm.bitcast %[[ARG0]] : vector<4xf16> to vector<2xi32>
+// CHECK:      %[[ELEM0:.*]] = llvm.extractelement %[[CAST1]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[ELEM1:.*]] = llvm.extractelement %[[CAST1]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      %[[PERM0_TUPLE:.*]] = rocdl.permlane16.swap %[[ELEM0]], %[[ELEM0]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM0:.*]] = llvm.extractvalue %[[PERM0_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[PERM1_TUPLE:.*]] = rocdl.permlane16.swap %[[ELEM1]], %[[ELEM1]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM1:.*]] = llvm.extractvalue %[[PERM1_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[VEC_INSERT0:.*]] = llvm.insertelement %[[PERM0]], %[[POISON]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[VEC_INSERT1:.*]] = llvm.insertelement %[[PERM1]], %[[VEC_INSERT0]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      %[[CAST2:.*]] = llvm.bitcast %[[VEC_INSERT1]] : vector<2xi32> to vector<4xf16>
+// CHECK:      return %[[CAST2]] : vector<4xf16>
+  %0 = amdgpu.permlane %arg0 swap_16 : vector<4xf16>
+  return %0 : vector<4xf16>
+}
+
+// CHECK-LABEL: func @test_permlane32_4xf16
+// CHECK-SAME: (%[[ARG0:.*]]: vector<4xf16>)
+func.func @test_permlane32_4xf16(%arg0 : vector<4xf16>) -> vector<4xf16> {
+// CHECK-DAG:  %[[POISON:.*]] = llvm.mlir.poison : vector<2xi32>
+// CHECK-DAG:  %[[C1:.*]] = llvm.mlir.constant(1 : i32) : i32
+// CHECK-DAG:  %[[C0:.*]] = llvm.mlir.constant(0 : i32) : i32
+// CHECK:      %[[CAST1:.*]] = llvm.bitcast %[[ARG0]] : vector<4xf16> to vector<2xi32>
+// CHECK:      %[[ELEM0:.*]] = llvm.extractelement %[[CAST1]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[ELEM1:.*]] = llvm.extractelement %[[CAST1]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      %[[PERM0_TUPLE:.*]] = rocdl.permlane32.swap %[[ELEM0]], %[[ELEM0]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM0:.*]] = llvm.extractvalue %[[PERM0_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[PERM1_TUPLE:.*]] = rocdl.permlane32.swap %[[ELEM1]], %[[ELEM1]], false, false : (i32, i32) -> <(i32, i32)>
+// CHECK:      %[[PERM1:.*]] = llvm.extractvalue %[[PERM1_TUPLE]][0] : !llvm.struct<(i32, i32)>
+// CHECK:      %[[VEC_INSERT0:.*]] = llvm.insertelement %[[PERM0]], %[[POISON]][%[[C0]] : i32] : vector<2xi32>
+// CHECK:      %[[VEC_INSERT1:.*]] = llvm.insertelement %[[PERM1]], %[[VEC_INSERT0]][%[[C1]] : i32] : vector<2xi32>
+// CHECK:      %[[CAST2:.*]] = llvm.bitcast %[[VEC_INSERT1]] : vector<2xi32> to vector<4xf16>
+// CHECK:      return %[[CAST2]] : vector<4xf16>
+  %0 = amdgpu.permlane %arg0 swap_32 : vector<4xf16>
+  return %0 : vector<4xf16>
+}
diff --git a/mlir/test/Dialect/AMDGPU/ops.mlir b/mlir/test/Dialect/AMDGPU/ops.mlir
index 87e11c028c62a..5eb6d53d4d9fe 100644
--- a/mlir/test/Dialect/AMDGPU/ops.mlir
+++ b/mlir/test/Dialect/AMDGPU/ops.mlir
@@ -524,6 +524,20 @@ func.func @swizzle_bitmode(%arg0 : f32) -> f32 {
   func.return %0 : f32
 }
 
+// CHECK-LABEL: func @permlane16_swap
+func.func @permlane16_swap(%arg0 : f32) -> f32 {
+  // CHECK: amdgpu.permlane
+  %0 = amdgpu.permlane %arg0 swap_16 : f32
+  func.return %0 : f32
+}
+
+// CHECK-LABEL: func @permlane32_swap
+func.func @permlane32_swap(%arg0 : f32) -> f32 {
+  // CHECK: amdgpu.permlane
+  %0 = amdgpu.permlane %arg0 swap_32 : f32
+  func.return %0 : f32
+}
+
 // CHECK-LABEL: func @scaled_mfma
 func.func @scaled_mfma(%arg0 : f8E8M0FNU, %arg1 : vector<32xf6E2M3FN>, %arg2 : vector<16xf32>) -> vector<16xf32> {
   // CHECK: amdgpu.scaled_mfma

>From fa28436f47c1528fbe223d160885b6b1a014dc90 Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Tue, 19 Aug 2025 10:34:19 -0500
Subject: [PATCH 2/8] expose boundCtrl and fi

---
 mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td       |  4 +++-
 mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp |  4 ++--
 mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir    | 10 ++++++++++
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
index 17386a2888788..019da46246841 100644
--- a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
+++ b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
@@ -671,7 +671,9 @@ def AMDGPU_PermlanePermAttr : EnumAttr<AMDGPU_Dialect, AMDGPU_PermlanePerm,
 
 def AMDGPU_PermlaneOp : AMDGPU_Op<"permlane", [Pure, AllTypesMatch<["result", "src"]>]>,
 Arguments<(ins AnyIntegerOrFloatOr1DVector:$src, 
-                AMDGPU_PermlanePermAttr:$kind)> {
+               AMDGPU_PermlanePermAttr:$kind,
+               DefaultValuedAttr<BoolAttr, "false">:$fi,
+               DefaultValuedAttr<BoolAttr, "false">:$bound_ctrl)> {
   let summary = "AMDGPU permlane op";
   let description = [{
     High-level wrapper on `rocdl.permlane` variants.
diff --git a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
index 4b0f8bcb40811..1f5c6bec92c42 100644
--- a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
+++ b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
@@ -1891,8 +1891,8 @@ struct AMDGPUPermlaneLowering : public ConvertOpToLLVMPattern<PermlaneOp> {
     Type i32 = rewriter.getI32Type();
     Value src = adaptor.getSrc();
     auto kind = op.getKind();
-    auto fi = rewriter.getBoolAttr(false);
-    auto boundctrl = rewriter.getBoolAttr(false);
+    auto fi = op.getFi();
+    auto boundctrl = op.getBoundCtrl();
 
     if (chipset < kGfx950)
       return op->emitOpError("permlane_swap is only supported on gfx950+");
diff --git a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
index 5b216e393043f..81b98c4e6bc3e 100644
--- a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
+++ b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
@@ -10,6 +10,16 @@ func.func @test_permlane16_i32(%arg0 : i32) -> i32 {
   return %0 : i32
 }
 
+// CHECK-LABEL: func @test_permlane16_i32_optional_attr
+// CHECK-SAME: (%[[ARG0:.*]]: i32)
+func.func @test_permlane16_i32_optional_attr(%arg0 : i32) -> i32 {
+// CHECK:  %[[PERM:.*]] = rocdl.permlane16.swap %[[ARG0]], %[[ARG0]], true, true : (i32, i32) -> <(i32, i32)>
+// CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
+// CHECK:  return %[[RES]] : i32
+  %0 = amdgpu.permlane %arg0 swap_16 { fi = true, bound_ctrl = true }  : i32
+  return %0 : i32
+}
+
 // CHECK-LABEL: func @test_permlane32_i32
 // CHECK-SAME: (%[[ARG0:.*]]: i32)
 func.func @test_permlane32_i32(%arg0 : i32) -> i32 {

>From 4bd1371cddc63e1bbb9ba1c25ebc738192b55aeb Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Wed, 20 Aug 2025 04:07:07 -0500
Subject: [PATCH 3/8] rename fi and replace auto with types

---
 mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp | 4 ++--
 mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir    | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
index 1f5c6bec92c42..66ade9eae4319 100644
--- a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
+++ b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
@@ -1891,8 +1891,8 @@ struct AMDGPUPermlaneLowering : public ConvertOpToLLVMPattern<PermlaneOp> {
     Type i32 = rewriter.getI32Type();
     Value src = adaptor.getSrc();
     auto kind = op.getKind();
-    auto fi = op.getFi();
-    auto boundctrl = op.getBoundCtrl();
+    bool fi = op.getFetchInactive();
+    bool boundctrl = op.getBoundCtrl();
 
     if (chipset < kGfx950)
       return op->emitOpError("permlane_swap is only supported on gfx950+");
diff --git a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
index 81b98c4e6bc3e..d341afa8b9077 100644
--- a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
+++ b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
@@ -16,7 +16,7 @@ func.func @test_permlane16_i32_optional_attr(%arg0 : i32) -> i32 {
 // CHECK:  %[[PERM:.*]] = rocdl.permlane16.swap %[[ARG0]], %[[ARG0]], true, true : (i32, i32) -> <(i32, i32)>
 // CHECK:  %[[RES:.*]] = llvm.extractvalue %[[PERM]][0] : !llvm.struct<(i32, i32)>
 // CHECK:  return %[[RES]] : i32
-  %0 = amdgpu.permlane %arg0 swap_16 { fi = true, bound_ctrl = true }  : i32
+  %0 = amdgpu.permlane %arg0 swap_16 { fetch_inactive = true, bound_ctrl = true }  : i32
   return %0 : i32
 }
 

>From 6b37a697e7116a05082a2b81c57f71ad9fb30545 Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Wed, 20 Aug 2025 04:07:27 -0500
Subject: [PATCH 4/8] improve docs

---
 mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td | 29 +++++++++++++++++--
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
index 019da46246841..2ccf6b4f46df6 100644
--- a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
+++ b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
@@ -672,14 +672,37 @@ def AMDGPU_PermlanePermAttr : EnumAttr<AMDGPU_Dialect, AMDGPU_PermlanePerm,
 def AMDGPU_PermlaneOp : AMDGPU_Op<"permlane", [Pure, AllTypesMatch<["result", "src"]>]>,
 Arguments<(ins AnyIntegerOrFloatOr1DVector:$src, 
                AMDGPU_PermlanePermAttr:$kind,
-               DefaultValuedAttr<BoolAttr, "false">:$fi,
+               DefaultValuedAttr<BoolAttr, "false">:$fetch_inactive,
                DefaultValuedAttr<BoolAttr, "false">:$bound_ctrl)> {
   let summary = "AMDGPU permlane op";
   let description = [{
-    High-level wrapper on `rocdl.permlane` variants.
+    High-level wrapper on `rocdl.permlane.*` variants.
 
     Supports arbitrary int/float/vector types, which will be repacked to i32 and
-    one or more `rocdl.permlane` ops during lowering.
+    one or more `rocdl.permlane.*` ops during lowering.
+    The following lane permutations are supported:
+    - Swap the data between odd and even rows of 16 lanes (`swap_16`)
+    - Swap the data between the first 32 lanes and the last 32 lanes (`swap_32`)
+
+    Format example:
+    ```
+    %0 = amdgpu.permlane %src swap_16 : f16
+    %1 = amdgpu.permlane %src swap_32 { fetch_inactive = true, bound_ctrl = true } : f16
+    ```
+
+    Operands:
+    * `$src`: Vector register to permute across lanes
+    * `$kind`: The kind of permutation operation.
+    * `$fetch_inactive`: Optional. Used to dertermine behavior of invalid lanes (disabled thread or out-of-range).
+      `fetch_inactive = false`: If source lane is invalid, use `bound_ctrl` to determine the source value.
+      `fetch_inactive = true`: If the source lane is disabled, fetch the source value anyway
+      (ignoring `bound_ctrl`). If the source lane is out-of-range, behavior is decided by `bound_ctrl`.
+    * `$bound_ctrl`: Optional. Used to determine what a thread should do if its source operand is from 
+      a disabled thread or invalid input: use the value zero, or disable the write.
+      `bound_ctrl = false`: Do not write when source is invalid or out-of-range.
+      `bound_ctrl = true`: Use zero as input if source is invalid or out-of-range
+
+    Note: Lowering is only supported on gfx950 and up.
   }];
   let results = (outs AnyIntegerOrFloatOr1DVector:$result);
   let assemblyFormat = [{

>From bde2253880e2ab5a016a9069900d2ad72757ac8c Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Wed, 20 Aug 2025 04:08:53 -0500
Subject: [PATCH 5/8] fix --

---
 mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
index d341afa8b9077..fa0049274d9cf 100644
--- a/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
+++ b/mlir/test/Conversion/AMDGPUToROCDL/permlane.mlir
@@ -1,4 +1,4 @@
-// RUN: mlir-opt -convert-amdgpu-to-rocdl=chipset=gfx950 --canonicalize %s | FileCheck %s
+// RUN: mlir-opt --convert-amdgpu-to-rocdl=chipset=gfx950 --canonicalize %s | FileCheck %s
 
 // CHECK-LABEL: func @test_permlane16_i32
 // CHECK-SAME: (%[[ARG0:.*]]: i32)

>From 417083833d287215e2b00e5fbe21ad4b44d69e9d Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Wed, 20 Aug 2025 04:09:44 -0500
Subject: [PATCH 6/8] move chipset check

---
 mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
index 66ade9eae4319..dda09edc805d9 100644
--- a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
+++ b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
@@ -1887,6 +1887,9 @@ struct AMDGPUPermlaneLowering : public ConvertOpToLLVMPattern<PermlaneOp> {
   LogicalResult
   matchAndRewrite(PermlaneOp op, OpAdaptor adaptor,
                   ConversionPatternRewriter &rewriter) const override {
+    if (chipset < kGfx950)
+      return op->emitOpError("permlane_swap is only supported on gfx950+");
+    
     Location loc = op.getLoc();
     Type i32 = rewriter.getI32Type();
     Value src = adaptor.getSrc();
@@ -1894,9 +1897,6 @@ struct AMDGPUPermlaneLowering : public ConvertOpToLLVMPattern<PermlaneOp> {
     bool fi = op.getFetchInactive();
     bool boundctrl = op.getBoundCtrl();
 
-    if (chipset < kGfx950)
-      return op->emitOpError("permlane_swap is only supported on gfx950+");
-
     SmallVector<Value> decomposed =
         LLVM::decomposeValue(rewriter, loc, src, i32);
 

>From 0373dad0c811b5e2757fa19ffe8f126572da0da4 Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Wed, 20 Aug 2025 04:55:57 -0500
Subject: [PATCH 7/8] clang format

---
 mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
index dda09edc805d9..605ab4ec757d1 100644
--- a/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
+++ b/mlir/lib/Conversion/AMDGPUToROCDL/AMDGPUToROCDL.cpp
@@ -1889,7 +1889,7 @@ struct AMDGPUPermlaneLowering : public ConvertOpToLLVMPattern<PermlaneOp> {
                   ConversionPatternRewriter &rewriter) const override {
     if (chipset < kGfx950)
       return op->emitOpError("permlane_swap is only supported on gfx950+");
-    
+
     Location loc = op.getLoc();
     Type i32 = rewriter.getI32Type();
     Value src = adaptor.getSrc();

>From 8f31b434361ec977579ce0f7ad7958f027bd6c38 Mon Sep 17 00:00:00 2001
From: Tim Gymnich <tim at gymni.ch>
Date: Thu, 21 Aug 2025 10:56:20 +0200
Subject: [PATCH 8/8] Update mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td

Co-authored-by: Jakub Kuderski <kubakuderski at gmail.com>
---
 mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
index 2ccf6b4f46df6..16d51ddc26969 100644
--- a/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
+++ b/mlir/include/mlir/Dialect/AMDGPU/IR/AMDGPU.td
@@ -691,7 +691,7 @@ Arguments<(ins AnyIntegerOrFloatOr1DVector:$src,
     ```
 
     Operands:
-    * `$src`: Vector register to permute across lanes
+    * `$src`: Vector register to permute across lanes of the subgroup.
     * `$kind`: The kind of permutation operation.
     * `$fetch_inactive`: Optional. Used to dertermine behavior of invalid lanes (disabled thread or out-of-range).
       `fetch_inactive = false`: If source lane is invalid, use `bound_ctrl` to determine the source value.



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