[llvm] [InstCombine] Canonicalise SextADD + GEP (PR #69581)

[via llvm-commits]

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@@ -0,0 +1,38 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+
+define void @test(ptr noundef %array2, i32 noundef signext %a, i32 noundef signext %b) {
+; CHECK-LABEL: define void @test(
+; CHECK-SAME: ptr noundef [[ARRAY2:%.*]], i32 noundef signext [[A:%.*]], i32 noundef signext [[B:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[ADD:%.*]] = add nsw i32 [[A]], 5
+; CHECK-NEXT:    [[IDXPROM:%.*]] = sext i32 [[ADD]] to i64
+; CHECK-NEXT:    [[SUB:%.*]] = add nsw i32 [[A]], 4
+; CHECK-NEXT:    [[IDXPROM1:%.*]] = sext i32 [[SUB]] to i64
+; CHECK-NEXT:    [[ARRAYIDX2:%.*]] = getelementptr inbounds [50 x i32], ptr [[ARRAY2]], i64 [[IDXPROM]], i64 [[IDXPROM1]]
+; CHECK-NEXT:    [[TMP0:%.*]] = load i32, ptr [[ARRAYIDX2]], align 4
+; CHECK-NEXT:    [[ADD3:%.*]] = add nsw i32 [[TMP0]], 1
+; CHECK-NEXT:    store i32 [[ADD3]], ptr [[ARRAYIDX2]], align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = sext i32 [[A]] to i64
+; CHECK-NEXT:    [[TMP2:%.*]] = getelementptr [50 x i32], ptr [[ARRAY2]], i64 [[TMP1]]
+; CHECK-NEXT:    [[ARRAYIDX8:%.*]] = getelementptr [50 x i32], ptr [[TMP2]], i64 25, i64 [[IDXPROM]]
+; CHECK-NEXT:    store i32 [[ADD]], ptr [[ARRAYIDX8]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  %add = add nsw i32 %a, 5
+  %idxprom = sext i32 %add to i64
+  %arrayidx = getelementptr inbounds [50 x i32], ptr %array2, i64 %idxprom
+  %sub = sub nsw i32 %add, 1
+  %idxprom1 = sext i32 %sub to i64
+  %arrayidx2 = getelementptr inbounds [50 x i32], ptr %arrayidx, i64 0, i64 %idxprom1
+  %0 = load i32, ptr %arrayidx2, align 4
+  %add3 = add nsw i32 %0, 1
+  store i32 %add3, ptr %arrayidx2, align 4
+  %add4 = add nsw i32 %add, 20
+  %idxprom5 = sext i32 %add4 to i64
+  %arrayidx6 = getelementptr inbounds [50 x i32], ptr %array2, i64 %idxprom5
+  %arrayidx8 = getelementptr inbounds [50 x i32], ptr %arrayidx6, i64 0, i64 %idxprom
+  store i32 %add, ptr %arrayidx8, align 4
+  ret void
+}
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LiqinWeng wrote:

done

https://github.com/llvm/llvm-project/pull/69581