[llvm] [Matrix] Propagate shape information through PHI insts (PR #141681)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,518 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -matrix-allow-contract=false -passes='lower-matrix-intrinsics' -S < %s | FileCheck %s
+
+define void @matrix_phi_loop(ptr %in1, ptr %in2, i32 %count, ptr %out) {
+; CHECK-LABEL: @matrix_phi_loop(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[COL_LOAD:%.*]] = load <3 x double>, ptr [[IN1:%.*]], align 128
+; CHECK-NEXT:    [[VEC_GEP:%.*]] = getelementptr double, ptr [[IN1]], i64 3
+; CHECK-NEXT:    [[COL_LOAD1:%.*]] = load <3 x double>, ptr [[VEC_GEP]], align 8
+; CHECK-NEXT:    [[VEC_GEP2:%.*]] = getelementptr double, ptr [[IN1]], i64 6
+; CHECK-NEXT:    [[COL_LOAD3:%.*]] = load <3 x double>, ptr [[VEC_GEP2]], align 16
+; CHECK-NEXT:    br label [[LOOP:%.*]]
+; CHECK:       loop:
+; CHECK-NEXT:    [[PHI9:%.*]] = phi <3 x double> [ [[COL_LOAD]], [[ENTRY:%.*]] ], [ [[TMP0:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[PHI10:%.*]] = phi <3 x double> [ [[COL_LOAD1]], [[ENTRY]] ], [ [[TMP1:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[PHI11:%.*]] = phi <3 x double> [ [[COL_LOAD3]], [[ENTRY]] ], [ [[TMP2:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[CTR:%.*]] = phi i32 [ [[COUNT:%.*]], [[ENTRY]] ], [ [[DEC:%.*]], [[LOOP]] ]
+; CHECK-NEXT:    [[COL_LOAD4:%.*]] = load <3 x double>, ptr [[IN2:%.*]], align 128
+; CHECK-NEXT:    [[VEC_GEP5:%.*]] = getelementptr double, ptr [[IN2]], i64 3
+; CHECK-NEXT:    [[COL_LOAD6:%.*]] = load <3 x double>, ptr [[VEC_GEP5]], align 8
+; CHECK-NEXT:    [[VEC_GEP7:%.*]] = getelementptr double, ptr [[IN2]], i64 6
+; CHECK-NEXT:    [[COL_LOAD8:%.*]] = load <3 x double>, ptr [[VEC_GEP7]], align 16
+; CHECK-NEXT:    [[TMP0]] = fadd <3 x double> [[PHI9]], [[COL_LOAD4]]
+; CHECK-NEXT:    [[TMP1]] = fadd <3 x double> [[PHI10]], [[COL_LOAD6]]
+; CHECK-NEXT:    [[TMP2]] = fadd <3 x double> [[PHI11]], [[COL_LOAD8]]
+; CHECK-NEXT:    [[DEC]] = sub i32 [[CTR]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[DEC]], 0
+; CHECK-NEXT:    br i1 [[CMP]], label [[EXIT:%.*]], label [[LOOP]]
+; CHECK:       exit:
+; CHECK-NEXT:    store <3 x double> [[TMP0]], ptr [[OUT:%.*]], align 128
+; CHECK-NEXT:    [[VEC_GEP12:%.*]] = getelementptr double, ptr [[OUT]], i64 3
+; CHECK-NEXT:    store <3 x double> [[TMP1]], ptr [[VEC_GEP12]], align 8
+; CHECK-NEXT:    [[VEC_GEP13:%.*]] = getelementptr double, ptr [[OUT]], i64 6
+; CHECK-NEXT:    store <3 x double> [[TMP2]], ptr [[VEC_GEP13]], align 16
+; CHECK-NEXT:    ret void
+;
+entry:
+  %mat = load <9 x double>, ptr %in1
+  br label %loop
+
+loop:
+  %phi = phi <9 x double> [%mat, %entry], [%sum, %loop]
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fhahn wrote:

Would also be good to have tests with phis with more than 2 incoming values and phis with other phis as incoming values

https://github.com/llvm/llvm-project/pull/141681