[Mlir-commits] [mlir] [mlir][spirv] Remove invalid canon pattern for GL.Length (PR #164301)

[llvmlistbot at llvm.org]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-mlir-spirv

Author: Jakub Kuderski (kuhar)

<details>
<summary>Changes</summary>

This rewrite does not preserve numerics: for example, we'd expect the maximum fp value to yield Inf instead of identity.

`GL.Length` does not allow for fast math flags, so we need to remove this. Special cases (constants) can be handled via a folder if someone wants to implement one.

---
Full diff: https://github.com/llvm/llvm-project/pull/164301.diff


3 Files Affected:

- (modified) mlir/lib/Dialect/SPIRV/IR/SPIRVCanonicalization.td (-8) 
- (modified) mlir/lib/Dialect/SPIRV/IR/SPIRVGLCanonicalization.cpp (+2-2) 
- (modified) mlir/test/Dialect/SPIRV/Transforms/gl-canonicalize.mlir (-22) 


``````````diff
diff --git a/mlir/lib/Dialect/SPIRV/IR/SPIRVCanonicalization.td b/mlir/lib/Dialect/SPIRV/IR/SPIRVCanonicalization.td
index 39fbab8f37a2e..e8d2274d29aa0 100644
--- a/mlir/lib/Dialect/SPIRV/IR/SPIRVCanonicalization.td
+++ b/mlir/lib/Dialect/SPIRV/IR/SPIRVCanonicalization.td
@@ -75,11 +75,3 @@ def ConvertComparisonIntoClamp2_#CmpClampPair[0] : Pat<
         )),
     (CmpClampPair[1] $input, $min, $max)>;
 }
-
-//===----------------------------------------------------------------------===//
-// spirv.GL.Length -> spirv.GL.FAbs
-//===----------------------------------------------------------------------===//
-
-def ConvertGLLengthToGLFAbs : Pat<
-    (SPIRV_GLLengthOp SPIRV_Float:$operand),
-    (SPIRV_GLFAbsOp $operand)>;
diff --git a/mlir/lib/Dialect/SPIRV/IR/SPIRVGLCanonicalization.cpp b/mlir/lib/Dialect/SPIRV/IR/SPIRVGLCanonicalization.cpp
index 46acb8c156fc6..3ad8057a58dc9 100644
--- a/mlir/lib/Dialect/SPIRV/IR/SPIRVGLCanonicalization.cpp
+++ b/mlir/lib/Dialect/SPIRV/IR/SPIRVGLCanonicalization.cpp
@@ -34,8 +34,8 @@ void populateSPIRVGLCanonicalizationPatterns(RewritePatternSet &results) {
               ConvertComparisonIntoClamp2_SPIRV_SLessThanOp,
               ConvertComparisonIntoClamp2_SPIRV_SLessThanEqualOp,
               ConvertComparisonIntoClamp2_SPIRV_ULessThanOp,
-              ConvertComparisonIntoClamp2_SPIRV_ULessThanEqualOp,
-              ConvertGLLengthToGLFAbs>(results.getContext());
+              ConvertComparisonIntoClamp2_SPIRV_ULessThanEqualOp>(
+      results.getContext());
 }
 } // namespace spirv
 } // namespace mlir
diff --git a/mlir/test/Dialect/SPIRV/Transforms/gl-canonicalize.mlir b/mlir/test/Dialect/SPIRV/Transforms/gl-canonicalize.mlir
index 33b877667512e..c1447b38f0a48 100644
--- a/mlir/test/Dialect/SPIRV/Transforms/gl-canonicalize.mlir
+++ b/mlir/test/Dialect/SPIRV/Transforms/gl-canonicalize.mlir
@@ -177,25 +177,3 @@ func.func @clamp_ulessthanequal(%input: i32, %min: i32, %max: i32) -> i32 {
   // CHECK-NEXT: spirv.ReturnValue [[RES]]
   spirv.ReturnValue %2 : i32
 }
-
-// -----
-
-//===----------------------------------------------------------------------===//
-// spirv.GL.Length
-//===----------------------------------------------------------------------===//
-
-// CHECK-LABEL: @convert_length_into_fabs_scalar
-func.func @convert_length_into_fabs_scalar(%arg0 : f32) -> f32 {
-  //CHECK: spirv.GL.FAbs {{%.*}} : f32
-  //CHECK-NOT: spirv.GL.Length
-  %0 = spirv.GL.Length %arg0 : f32 -> f32
-  spirv.ReturnValue %0 : f32
-}
-
-// CHECK-LABEL: @dont_convert_length_into_fabs_vec
-func.func @dont_convert_length_into_fabs_vec(%arg0 : vector<3xf32>) -> f32 {
-  //CHECK: spirv.GL.Length {{%.*}} : vector<3xf32> -> f32
-  //CHECK-NOT: spirv.GL.FAbs
-  %0 = spirv.GL.Length %arg0 : vector<3xf32> -> f32
-  spirv.ReturnValue %0 : f32
-}

``````````

</details>


https://github.com/llvm/llvm-project/pull/164301