[clang] [CIR] Implement support for MatrixSingleSubstract expr (PR #232079)

[Erich Keane via cfe-commits]

================
@@ -6636,22 +6635,25 @@ def CIR_MatrixExtractOp : CIR_Op<"matrix.extract", [
     ```
     %rowIdx = cir.const #cir.int<1> : !u64i
     %columnIdx = cir.const #cir.int<2> : !u64i
-    %element = cir.matrix.extract %matrix[%rowIdx : !u64i] [%columnIdx : !u64i] 
+    %row = cir.matrix.extract %matrix[%rowIdx : !s32i] 
----------------
erichkeane wrote:

Why are the types of the rowIdx/columnIdx different in these lines, but still declared u64i? 

https://github.com/llvm/llvm-project/pull/232079