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

[via llvm-commits]

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@@ -0,0 +1,82 @@
+; 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 %ptr, i32 noundef signext %a, i32 noundef signext %b) {
+; CHECK-LABEL: define void @test(
+; CHECK-SAME: ptr noundef [[PTR:%.*]], i32 noundef signext [[A:%.*]], i32 noundef signext [[B:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = sext i32 [[A]] to i64
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i32, ptr [[PTR]], i64 [[TMP0]]
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i32, ptr [[TMP1]], i64 10
+; CHECK-NEXT:    store i32 [[B]], ptr [[GEP]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  %add = add nsw i32 %a, 10
+  %idx = sext i32 %add to i64
+  %gep = getelementptr inbounds i32, ptr %ptr, i64 %idx
+  store i32 %b, ptr %gep
+  ret void
+}
+
+define void @test_add_res_moreoneuse(ptr noundef %ptr, i32 noundef signext %a, i32 noundef signext %b) {
+; CHECK-LABEL: define void @test_add_res_moreoneuse(
+; CHECK-SAME: ptr noundef [[PTR:%.*]], i32 noundef signext [[A:%.*]], i32 noundef signext [[B:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[ADD:%.*]] = add nsw i32 [[A]], 5
+; CHECK-NEXT:    [[IDX:%.*]] = sext i32 [[ADD]] to i64
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds i32, ptr [[PTR]], i64 [[IDX]]
+; CHECK-NEXT:    store i32 [[B]], ptr [[GEP]], align 4
+; CHECK-NEXT:    [[TMP0:%.*]] = sext i32 [[A]] to i64
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr i32, ptr [[PTR]], i64 [[TMP0]]
+; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr i32, ptr [[TMP1]], i64 35
+; CHECK-NEXT:    store i32 [[ADD]], ptr [[GEP1]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  %add = add nsw i32 %a, 5
+  %idx = sext i32 %add to i64
+  %gep= getelementptr inbounds i32, ptr %ptr, i64 %idx
+  store i32 %b, ptr %gep
+  %add1 = add nsw i32 %add, 30
+  %idx1 = sext i32 %add1 to i64
+  %gep1 = getelementptr inbounds i32, ptr %ptr, i64 %idx1
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LiqinWeng wrote:

done

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