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[InstCombine] Thwart complexity-based canonicalization in shl-add test (NFC) #91413

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Merged
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May 9, 2024
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[InstCombine] Thwart complexity-based canonicalization in shl-add test (NFC) #91413

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6 changes: 4 additions & 2 deletions llvm/test/Transforms/InstCombine/lshr.ll
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Original file line number Diff line number Diff line change
Expand Up @@ -397,12 +397,14 @@ define i32 @shl_add_lshr(i32 %x, i32 %c, i32 %y) {

define i32 @shl_add_lshr_comm(i32 %x, i32 %c, i32 %y) {
; CHECK-LABEL: @shl_add_lshr_comm(
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[Y:%.*]], [[C:%.*]]
; CHECK-NEXT: [[Y2:%.*]] = mul i32 [[Y:%.*]], [[Y]]
; CHECK-NEXT: [[TMP1:%.*]] = lshr i32 [[Y2]], [[C:%.*]]
; CHECK-NEXT: [[LSHR:%.*]] = add nuw i32 [[TMP1]], [[X:%.*]]
; CHECK-NEXT: ret i32 [[LSHR]]
;
%shl = shl nuw i32 %x, %c
%add = add nuw i32 %y, %shl
%y2 = mul i32 %y, %y ; thwart complexity-based canonicalization
%add = add nuw i32 %y2, %shl
%lshr = lshr i32 %add, %c
ret i32 %lshr
}
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