[Mlir-commits] [mlir] 7380050 - [mlir][VectorToLLVM] Use the converted index type in vector.type_cast (#218742)

[llvmlistbot at llvm.org]

Author: Christian Ulmann
Date: 2026-08-26T09:50:38+02:00
New Revision: 7380050ae1a8261400350dd08a952ad3f00db1b3

URL: https://github.com/llvm/llvm-project/commit/7380050ae1a8261400350dd08a952ad3f00db1b3
DIFF: https://github.com/llvm/llvm-project/commit/7380050ae1a8261400350dd08a952ad3f00db1b3.diff

LOG: [mlir][VectorToLLVM] Use the converted index type in vector.type_cast (#218742)

`VectorTypeCastOpConversion` hardcoded `i64` for the offset, size and
stride constants it inserts into the target memref descriptor, while the
descriptor's fields have the converted index type. With a type converter
configured for a 32-bit index the pattern therefore emitted invalid IR:

```
'llvm.insertvalue' op Type mismatch: cannot insert 'i64' into
'!llvm.struct<(ptr, ptr, i32)>'
```

Build the constants from the converted index type instead.

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply at anthropic.com>

Added: 
    mlir/test/Conversion/VectorToLLVM/vector-to-llvm-32b.mlir

Modified: 
    mlir/lib/Conversion/VectorToLLVM/ConvertVectorToLLVM.cpp

Removed: 
    


################################################################################
diff  --git a/mlir/lib/Conversion/VectorToLLVM/ConvertVectorToLLVM.cpp b/mlir/lib/Conversion/VectorToLLVM/ConvertVectorToLLVM.cpp
index 54c117bae476b..98d701147e3dc 100644
--- a/mlir/lib/Conversion/VectorToLLVM/ConvertVectorToLLVM.cpp
+++ b/mlir/lib/Conversion/VectorToLLVM/ConvertVectorToLLVM.cpp
@@ -1479,7 +1479,9 @@ class VectorTypeCastOpConversion
     if (llvm::any_of(*targetStrides, ShapedType::isDynamic))
       return failure();
 
-    auto int64Ty = IntegerType::get(rewriter.getContext(), 64);
+    // The offset, size and stride fields of a memref descriptor use the
+    // converted index type.
+    Type indexTy = getTypeConverter()->getIndexType();
 
     // Create descriptor.
     auto desc = MemRefDescriptor::poison(rewriter, loc, llvmTargetDescriptorTy);
@@ -1491,23 +1493,19 @@ class VectorTypeCastOpConversion
     Value ptr = sourceMemRef.alignedPtr(rewriter, loc);
     desc.setAlignedPtr(rewriter, loc, ptr);
     // Fill offset 0.
-    auto attr = rewriter.getIntegerAttr(rewriter.getIndexType(), 0);
-    auto zero = LLVM::ConstantOp::create(rewriter, loc, int64Ty, attr);
-    desc.setOffset(rewriter, loc, zero);
+    desc.setOffset(rewriter, loc,
+                   LLVM::createIndexAttrConstant(rewriter, loc, indexTy, 0));
 
     // Fill size and stride descriptors in memref.
     for (const auto &indexedSize :
          llvm::enumerate(targetMemRefType.getShape())) {
       int64_t index = indexedSize.index();
-      auto sizeAttr =
-          rewriter.getIntegerAttr(rewriter.getIndexType(), indexedSize.value());
-      auto size = LLVM::ConstantOp::create(rewriter, loc, int64Ty, sizeAttr);
-      desc.setSize(rewriter, loc, index, size);
-      auto strideAttr = rewriter.getIntegerAttr(rewriter.getIndexType(),
-                                                (*targetStrides)[index]);
-      auto stride =
-          LLVM::ConstantOp::create(rewriter, loc, int64Ty, strideAttr);
-      desc.setStride(rewriter, loc, index, stride);
+      desc.setSize(rewriter, loc, index,
+                   LLVM::createIndexAttrConstant(rewriter, loc, indexTy,
+                                                 indexedSize.value()));
+      desc.setStride(rewriter, loc, index,
+                     LLVM::createIndexAttrConstant(rewriter, loc, indexTy,
+                                                   (*targetStrides)[index]));
     }
 
     rewriter.replaceOp(castOp, {desc});

diff  --git a/mlir/test/Conversion/VectorToLLVM/vector-to-llvm-32b.mlir b/mlir/test/Conversion/VectorToLLVM/vector-to-llvm-32b.mlir
new file mode 100644
index 0000000000000..f7ff7d6be2ffb
--- /dev/null
+++ b/mlir/test/Conversion/VectorToLLVM/vector-to-llvm-32b.mlir
@@ -0,0 +1,17 @@
+// The memref descriptor fields use the converted index type, which is not
+// necessarily `i64`. Note that dynamic=true is needed to ensure that the data
+// layout is considered.
+
+// RUN: mlir-opt %s --convert-to-llvm="dynamic=true" | FileCheck %s
+
+module attributes {dlti.dl_spec = #dlti.dl_spec<
+  #dlti.dl_entry<index, 32>
+>} {
+  // CHECK-LABEL: llvm.func @type_cast
+  //       CHECK:   %[[OFFSET:.*]] = llvm.mlir.constant(0 : index) : i32
+  //       CHECK:   llvm.insertvalue %[[OFFSET]], %{{.*}}[2] : !llvm.struct<(ptr, ptr, i32)>
+  func.func @type_cast(%arg0: memref<8x8x8xf32>) -> memref<vector<8x8x8xf32>> {
+    %0 = vector.type_cast %arg0 : memref<8x8x8xf32> to memref<vector<8x8x8xf32>>
+    return %0 : memref<vector<8x8x8xf32>>
+  }
+}