knownzero-shift.ll
2.59 KB
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -instsimplify -S < %s | FileCheck %s
define i1 @test(i8 %p, i8* %pq) {
; CHECK-LABEL: @test(
; CHECK-NEXT: ret i1 false
;
%q = load i8, i8* %pq, !range !0 ; %q is known nonzero; no known bits
%1 = or i8 %p, 2 ; %1[1] = 1
%2 = and i8 %1, 254 ; %2[0] = 0, %2[1] = 1
%A = lshr i8 %2, 1 ; We should know that %A is nonzero.
%x = icmp eq i8 %A, 0
ret i1 %x
}
!0 = !{ i8 1, i8 5 }
; The following cases only get folded by InstCombine,
; see InstCombine/shift-shift.ll. If we wanted to,
; we could explicitly handle them in InstSimplify as well.
define i32 @shl_shl(i32 %A) {
; CHECK-LABEL: @shl_shl(
; CHECK-NEXT: [[B:%.*]] = shl i32 [[A:%.*]], 6
; CHECK-NEXT: [[C:%.*]] = shl i32 [[B]], 28
; CHECK-NEXT: ret i32 [[C]]
;
%B = shl i32 %A, 6
%C = shl i32 %B, 28
ret i32 %C
}
define <2 x i33> @shl_shl_splat_vec(<2 x i33> %A) {
; CHECK-LABEL: @shl_shl_splat_vec(
; CHECK-NEXT: [[B:%.*]] = shl <2 x i33> [[A:%.*]], <i33 5, i33 5>
; CHECK-NEXT: [[C:%.*]] = shl <2 x i33> [[B]], <i33 28, i33 28>
; CHECK-NEXT: ret <2 x i33> [[C]]
;
%B = shl <2 x i33> %A, <i33 5, i33 5>
%C = shl <2 x i33> %B, <i33 28, i33 28>
ret <2 x i33> %C
}
; FIXME
define <2 x i33> @shl_shl_vec(<2 x i33> %A) {
; CHECK-LABEL: @shl_shl_vec(
; CHECK-NEXT: [[B:%.*]] = shl <2 x i33> [[A:%.*]], <i33 6, i33 5>
; CHECK-NEXT: [[C:%.*]] = shl <2 x i33> [[B]], <i33 27, i33 28>
; CHECK-NEXT: ret <2 x i33> [[C]]
;
%B = shl <2 x i33> %A, <i33 6, i33 5>
%C = shl <2 x i33> %B, <i33 27, i33 28>
ret <2 x i33> %C
}
define i232 @lshr_lshr(i232 %A) {
; CHECK-LABEL: @lshr_lshr(
; CHECK-NEXT: [[B:%.*]] = lshr i232 [[A:%.*]], 231
; CHECK-NEXT: [[C:%.*]] = lshr i232 [[B]], 1
; CHECK-NEXT: ret i232 [[C]]
;
%B = lshr i232 %A, 231
%C = lshr i232 %B, 1
ret i232 %C
}
define <2 x i32> @lshr_lshr_splat_vec(<2 x i32> %A) {
; CHECK-LABEL: @lshr_lshr_splat_vec(
; CHECK-NEXT: [[B:%.*]] = lshr <2 x i32> [[A:%.*]], <i32 28, i32 28>
; CHECK-NEXT: [[C:%.*]] = lshr <2 x i32> [[B]], <i32 4, i32 4>
; CHECK-NEXT: ret <2 x i32> [[C]]
;
%B = lshr <2 x i32> %A, <i32 28, i32 28>
%C = lshr <2 x i32> %B, <i32 4, i32 4>
ret <2 x i32> %C
}
define <2 x i32> @lshr_lshr_vec(<2 x i32> %A) {
; CHECK-LABEL: @lshr_lshr_vec(
; CHECK-NEXT: [[B:%.*]] = lshr <2 x i32> [[A:%.*]], <i32 29, i32 28>
; CHECK-NEXT: [[C:%.*]] = lshr <2 x i32> [[B]], <i32 4, i32 5>
; CHECK-NEXT: ret <2 x i32> [[C]]
;
%B = lshr <2 x i32> %A, <i32 29, i32 28>
%C = lshr <2 x i32> %B, <i32 4, i32 5>
ret <2 x i32> %C
}