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; RUN: opt < %s -instsimplify -S | FileCheck %s
; PR8862
define i32 @shift1(i32 %A, i32 %B) {
; CHECK-LABEL: @shift1(
; CHECK-NEXT: ret i32 %A
;
%C = lshr exact i32 %A, %B
%D = shl nuw i32 %C, %B
ret i32 %D
}
define i32 @shift2(i32 %A, i32 %B) {
; CHECK-LABEL: @shift2(
; CHECK-NEXT: [[C:%.*]] = lshr i32 %A, %B
; CHECK-NEXT: [[D:%.*]] = shl nuw i32 [[C]], %B
; CHECK-NEXT: ret i32 [[D]]
;
%C = lshr i32 %A, %B
%D = shl nuw i32 %C, %B
ret i32 %D
}
define i32 @shift3(i32 %A, i32 %B) {
; CHECK-LABEL: @shift3(
; CHECK-NEXT: ret i32 %A
;
%C = ashr exact i32 %A, %B
%D = shl nuw i32 %C, %B
ret i32 %D
}
define i32 @shift4(i32 %A, i32 %B) {
; CHECK-LABEL: @shift4(
; CHECK-NEXT: ret i32 %A
;
%C = shl nuw i32 %A, %B
%D = lshr i32 %C, %B
ret i32 %D
}
define i32 @shift5(i32 %A, i32 %B) {
; CHECK-LABEL: @shift5(
; CHECK-NEXT: ret i32 %A
;
%C = shl nsw i32 %A, %B
%D = ashr i32 %C, %B
ret i32 %D
}
define i32 @div1(i32 %V) {
; CHECK-LABEL: @div1(
; CHECK-NEXT: ret i32 0
;
%A = udiv i32 %V, -2147483648
%B = udiv i32 %A, -2147483648
ret i32 %B
}
define i32 @div2(i32 %V) {
; CHECK-LABEL: @div2(
; CHECK-NEXT: ret i32 0
;
%A = sdiv i32 %V, -1
%B = sdiv i32 %A, -2147483648
ret i32 %B
}
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