[mlir][MemRef] fix error message in ReinterpretCastOp::verify

[ubfx]

Summary

The error message that is displayed when the offset in the MemRefType of
the Op's result is unexpected was the wrong way around, mixing up
expected and actual offset.

[ubfx]

Also fix the tests

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Thank you, @ftynse
Could you push the patch when you get a chance since I don't have permissions?

mlir/lib/Dialect/MemRef/IR/MemRefOps.cpp

return emitError("expected result type to have strided layout but found ")
            << resultType;
 
   // Match offset in result memref type and in static_offsets attribute.
   int64_t expectedOffset = getStaticOffsets().front();
   if (!ShapedType::isDynamic(resultOffset) &&
       !ShapedType::isDynamic(expectedOffset) &&
       resultOffset != expectedOffset)
     return emitError("expected result type with offset = ")
-           << resultOffset << " instead of " << expectedOffset;
+           << expectedOffset << " instead of " << resultOffset;
 
   // Match strides in result memref type and in static_strides attribute.
   for (auto [idx, resultStride, expectedStride] :
        llvm::enumerate(resultStrides, getStaticStrides())) {
     if (!ShapedType::isDynamic(resultStride) &&
         !ShapedType::isDynamic(expectedStride) &&
         resultStride != expectedStride)
       return emitError("expected result type with stride = ")

mlir/test/Dialect/MemRef/invalid.mlir

%out = memref.reinterpret_cast %in to
            offset: [0], sizes: [10], strides: [1]
          : memref<*xf32> to memref<10xi32, strided<[1], offset: 0>, 2>
   return
 }
 
 // -----
 
 func.func @memref_reinterpret_cast_offset_mismatch(%in: memref<?xf32>) {
-  // expected-error @+1 {{expected result type with offset = 2 instead of 1}}
+  // expected-error @+1 {{expected result type with offset = 1 instead of 2}}
   %out = memref.reinterpret_cast %in to
            offset: [1], sizes: [10], strides: [1]
          : memref<?xf32> to memref<10xf32, strided<[1], offset: 2>>
   return
 }
 
 // -----
 
%out = memref.reinterpret_cast %in to
            offset: [2], sizes: [10], strides: [2]
          : memref<?xf32> to memref<10xf32, strided<[1], offset: 2>>
   return
 }
 
 // -----
 
 func.func @memref_reinterpret_cast_no_map_but_offset(%in: memref<?xf32>) {
-  // expected-error @+1 {{expected result type with offset = 0 instead of 2}}
+  // expected-error @+1 {{expected result type with offset = 2 instead of 0}}
   %out = memref.reinterpret_cast %in to offset: [2], sizes: [10], strides: [1]
          : memref<?xf32> to memref<10xf32>
   return
 }
 
 // -----
 
 func.func @memref_reinterpret_cast_no_map_but_stride(%in: memref<?xf32>) {