[llvm] [DAG] Replace DAGCombiner::ConstantFoldBITCASTofBUILD_VECTOR with SelectionDAG::FoldConstantBuildVector (PR #147037)

[Simon Pilgrim via llvm-commits]

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@@ -5,18 +5,19 @@ define amdgpu_kernel void @test_iglp_opt_rev_mfma_gemm(<1 x i64> %L1) {
 ; GCN-LABEL: test_iglp_opt_rev_mfma_gemm:
 ; GCN:       ; %bb.0: ; %entry
 ; GCN-NEXT:    v_mov_b32_e32 v32, 0
+; GCN-NEXT:    ds_read_b128 v[0:3], v32
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RKSimon wrote:

I converted the code to be recursive to make error handling easier and it now shares a common SDLoc

https://github.com/llvm/llvm-project/pull/147037