[llvm] [SLP]Represent externally used values as original scalars, if profitable. (PR #100904)

[Simon Pilgrim via llvm-commits]

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@@ -5,18 +5,18 @@ define void @test() {
 ; CHECK-LABEL: define void @test() {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[IDX2:%.*]] = getelementptr [1000 x i64], ptr null, i64 0, i64 7
-; CHECK-NEXT:    [[TMP0:%.*]] = load <8 x i64>, ptr [[IDX2]], align 8
 ; CHECK-NEXT:    [[TMP1:%.*]] = load <8 x i64>, ptr [[IDX2]], align 8
+; CHECK-NEXT:    [[TMP2:%.*]] = load <8 x i64>, ptr [[IDX2]], align 8
 ; CHECK-NEXT:    [[TMP3:%.*]] = load i64, ptr null, align 8
 ; CHECK-NEXT:    br label [[LOOP:%.*]]
 ; CHECK:       loop:
 ; CHECK-NEXT:    [[PHI1:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[OP_RDX25:%.*]], [[LOOP]] ]
-; CHECK-NEXT:    [[TMP6:%.*]] = phi <8 x i64> [ [[TMP0]], [[ENTRY]] ], [ [[TMP1]], [[LOOP]] ]
-; CHECK-NEXT:    [[TMP7:%.*]] = mul <8 x i64> [[TMP6]], <i64 4, i64 4, i64 4, i64 4, i64 4, i64 4, i64 4, i64 4>
-; CHECK-NEXT:    [[TMP5:%.*]] = mul <8 x i64> [[TMP1]], <i64 2, i64 2, i64 2, i64 2, i64 2, i64 2, i64 2, i64 2>
-; CHECK-NEXT:    [[TMP9:%.*]] = call i64 @llvm.vector.reduce.add.v8i64(<8 x i64> [[TMP7]])
+; CHECK-NEXT:    [[TMP4:%.*]] = phi <8 x i64> [ [[TMP1]], [[ENTRY]] ], [ [[TMP2]], [[LOOP]] ]
+; CHECK-NEXT:    [[TMP6:%.*]] = mul <8 x i64> [[TMP4]], <i64 4, i64 4, i64 4, i64 4, i64 4, i64 4, i64 4, i64 4>
+; CHECK-NEXT:    [[TMP5:%.*]] = mul <8 x i64> [[TMP2]], <i64 2, i64 2, i64 2, i64 2, i64 2, i64 2, i64 2, i64 2>
+; CHECK-NEXT:    [[TMP7:%.*]] = call i64 @llvm.vector.reduce.add.v8i64(<8 x i64> [[TMP6]])
 ; CHECK-NEXT:    [[TMP8:%.*]] = call i64 @llvm.vector.reduce.add.v8i64(<8 x i64> [[TMP5]])
-; CHECK-NEXT:    [[OP_RDX16:%.*]] = add i64 [[TMP9]], [[TMP8]]
+; CHECK-NEXT:    [[OP_RDX16:%.*]] = add i64 [[TMP7]], [[TMP8]]
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RKSimon wrote:

NFC?

https://github.com/llvm/llvm-project/pull/100904