[llvm] [Matrix] Propagate shape information through Select insts (PR #141876)

[Jon Roelofs via llvm-commits]

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@@ -0,0 +1,75 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -passes='lower-matrix-intrinsics' -S < %s | FileCheck %s
+
+define void @select_2x2_bot(i1 %cond, ptr %lhs, ptr %rhs, ptr %out) {
+; CHECK-LABEL: @select_2x2_bot(
+; CHECK-NEXT:    [[COL_LOAD:%.*]] = load <2 x float>, ptr [[LHS:%.*]], align 16
+; CHECK-NEXT:    [[VEC_GEP:%.*]] = getelementptr float, ptr [[LHS]], i64 2
+; CHECK-NEXT:    [[COL_LOAD1:%.*]] = load <2 x float>, ptr [[VEC_GEP]], align 8
+; CHECK-NEXT:    [[COL_LOAD2:%.*]] = load <2 x float>, ptr [[RHS:%.*]], align 16
+; CHECK-NEXT:    [[VEC_GEP3:%.*]] = getelementptr float, ptr [[RHS]], i64 2
+; CHECK-NEXT:    [[COL_LOAD4:%.*]] = load <2 x float>, ptr [[VEC_GEP3]], align 8
+; CHECK-NEXT:    [[TMP1:%.*]] = select i1 [[COND:%.*]], <2 x float> [[COL_LOAD]], <2 x float> [[COL_LOAD2]]
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[COND]], <2 x float> [[COL_LOAD1]], <2 x float> [[COL_LOAD4]]
+; CHECK-NEXT:    store <2 x float> [[TMP1]], ptr [[OUT:%.*]], align 16
+; CHECK-NEXT:    [[VEC_GEP5:%.*]] = getelementptr float, ptr [[OUT]], i64 2
+; CHECK-NEXT:    store <2 x float> [[TMP2]], ptr [[VEC_GEP5]], align 8
+; CHECK-NEXT:    ret void
+;
+  %lhsv = load <4 x float>, ptr %lhs
+  %rhsv = load <4 x float>, ptr %rhs
+  %op = select i1 %cond, <4 x float> %lhsv, <4 x float> %rhsv
+  %opt  = call <4 x float> @llvm.matrix.transpose(<4 x float> %op, i32 2, i32 2)
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jroelofs wrote:

- [] use column major store for shape info

https://github.com/llvm/llvm-project/pull/141876