llvm-6502/test/Transforms/InstCombine/icmp-shr.ll
Andrea Di Biagio c53401ee91 [InstCombine] Fix wrong folding of constant comparisons involving ashr and negative values.
This patch fixes a bug in method InstCombiner::FoldCmpCstShrCst where we
wrongly computed the distance between the highest bits set of two negative
values.

This fixes PR21222.

Differential Revision: http://reviews.llvm.org/D5700


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219406 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 12:41:49 +00:00

699 lines
16 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
target datalayout = "e-p:64:64:64-p1:16:16:16-p2:32:32:32-p3:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
; CHECK-LABEL: @exact_lshr_eq_both_zero
; CHECK-NEXT: ret i1 true
define i1 @exact_lshr_eq_both_zero(i8 %a) {
%shr = lshr exact i8 0, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_both_zero
; CHECK-NEXT: ret i1 true
define i1 @exact_ashr_eq_both_zero(i8 %a) {
%shr = ashr exact i8 0, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq_both_zero
; CHECK-NEXT: ret i1 true
define i1 @nonexact_lshr_eq_both_zero(i8 %a) {
%shr = lshr i8 0, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq_both_zero
; CHECK-NEXT: ret i1 true
define i1 @nonexact_ashr_eq_both_zero(i8 %a) {
%shr = ashr i8 0, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_both_zero
; CHECK-NEXT: ret i1 false
define i1 @exact_lshr_ne_both_zero(i8 %a) {
%shr = lshr exact i8 0, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_both_zero
; CHECK-NEXT: ret i1 false
define i1 @exact_ashr_ne_both_zero(i8 %a) {
%shr = ashr exact i8 0, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne_both_zero
; CHECK-NEXT: ret i1 false
define i1 @nonexact_lshr_ne_both_zero(i8 %a) {
%shr = lshr i8 0, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne_both_zero
; CHECK-NEXT: ret i1 false
define i1 @nonexact_ashr_ne_both_zero(i8 %a) {
%shr = ashr i8 0, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_last_zero
; CHECK-NEXT: ret i1 false
define i1 @exact_lshr_eq_last_zero(i8 %a) {
%shr = lshr exact i8 128, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_last_zero
; CHECK-NEXT: ret i1 false
define i1 @exact_ashr_eq_last_zero(i8 %a) {
%shr = ashr exact i8 -128, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_last_zero
; CHECK-NEXT: ret i1 true
define i1 @exact_lshr_ne_last_zero(i8 %a) {
%shr = lshr exact i8 128, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_last_zero
; CHECK-NEXT: ret i1 true
define i1 @exact_ashr_ne_last_zero(i8 %a) {
%shr = ashr exact i8 -128, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq_last_zero
; CHECK-NEXT: ret i1 false
define i1 @nonexact_lshr_eq_last_zero(i8 %a) {
%shr = lshr i8 128, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq_last_zero
; CHECK-NEXT: ret i1 false
define i1 @nonexact_ashr_eq_last_zero(i8 %a) {
%shr = ashr i8 -128, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne_last_zero
; CHECK-NEXT: ret i1 true
define i1 @nonexact_lshr_ne_last_zero(i8 %a) {
%shr = lshr i8 128, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne_last_zero
; CHECK-NEXT: ret i1 true
define i1 @nonexact_ashr_ne_last_zero(i8 %a) {
%shr = ashr i8 -128, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @lshr_eq_msb_low_last_zero
; CHECK-NEXT: icmp ugt i8 %a, 6
define i1 @lshr_eq_msb_low_last_zero(i8 %a) {
%shr = lshr i8 127, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @ashr_eq_msb_low_second_zero
; CHECK-NEXT: icmp ugt i8 %a, 6
define i1 @ashr_eq_msb_low_second_zero(i8 %a) {
%shr = ashr i8 127, %a
%cmp = icmp eq i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @lshr_ne_msb_low_last_zero
; CHECK-NEXT: icmp ult i8 %a, 7
define i1 @lshr_ne_msb_low_last_zero(i8 %a) {
%shr = lshr i8 127, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @ashr_ne_msb_low_second_zero
; CHECK-NEXT: icmp ult i8 %a, 7
define i1 @ashr_ne_msb_low_second_zero(i8 %a) {
%shr = ashr i8 127, %a
%cmp = icmp ne i8 %shr, 0
ret i1 %cmp
}
; CHECK-LABEL: @lshr_eq_first_zero
; CHECK-NEXT: ret i1 false
define i1 @lshr_eq_first_zero(i8 %a) {
%shr = lshr i8 0, %a
%cmp = icmp eq i8 %shr, 2
ret i1 %cmp
}
; CHECK-LABEL: @ashr_eq_first_zero
; CHECK-NEXT: ret i1 false
define i1 @ashr_eq_first_zero(i8 %a) {
%shr = ashr i8 0, %a
%cmp = icmp eq i8 %shr, 2
ret i1 %cmp
}
; CHECK-LABEL: @lshr_ne_first_zero
; CHECK-NEXT: ret i1 true
define i1 @lshr_ne_first_zero(i8 %a) {
%shr = lshr i8 0, %a
%cmp = icmp ne i8 %shr, 2
ret i1 %cmp
}
; CHECK-LABEL: @ashr_ne_first_zero
; CHECK-NEXT: ret i1 true
define i1 @ashr_ne_first_zero(i8 %a) {
%shr = ashr i8 0, %a
%cmp = icmp ne i8 %shr, 2
ret i1 %cmp
}
; CHECK-LABEL: @ashr_eq_both_minus1
; CHECK-NEXT: ret i1 true
define i1 @ashr_eq_both_minus1(i8 %a) {
%shr = ashr i8 -1, %a
%cmp = icmp eq i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @ashr_ne_both_minus1
; CHECK-NEXT: ret i1 false
define i1 @ashr_ne_both_minus1(i8 %a) {
%shr = ashr i8 -1, %a
%cmp = icmp ne i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_both_minus1
; CHECK-NEXT: ret i1 true
define i1 @exact_ashr_eq_both_minus1(i8 %a) {
%shr = ashr exact i8 -1, %a
%cmp = icmp eq i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_both_minus1
; CHECK-NEXT: ret i1 false
define i1 @exact_ashr_ne_both_minus1(i8 %a) {
%shr = ashr exact i8 -1, %a
%cmp = icmp ne i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @ashr_eq_both_equal
; CHECK-NEXT: icmp eq i8 %a, 0
define i1 @ashr_eq_both_equal(i8 %a) {
%shr = ashr i8 128, %a
%cmp = icmp eq i8 %shr, 128
ret i1 %cmp
}
; CHECK-LABEL: @ashr_ne_both_equal
; CHECK-NEXT: icmp ne i8 %a, 0
define i1 @ashr_ne_both_equal(i8 %a) {
%shr = ashr i8 128, %a
%cmp = icmp ne i8 %shr, 128
ret i1 %cmp
}
; CHECK-LABEL: @lshr_eq_both_equal
; CHECK-NEXT: icmp eq i8 %a, 0
define i1 @lshr_eq_both_equal(i8 %a) {
%shr = lshr i8 127, %a
%cmp = icmp eq i8 %shr, 127
ret i1 %cmp
}
; CHECK-LABEL: @lshr_ne_both_equal
; CHECK-NEXT: icmp ne i8 %a, 0
define i1 @lshr_ne_both_equal(i8 %a) {
%shr = lshr i8 127, %a
%cmp = icmp ne i8 %shr, 127
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_both_equal
; CHECK-NEXT: icmp eq i8 %a, 0
define i1 @exact_ashr_eq_both_equal(i8 %a) {
%shr = ashr exact i8 128, %a
%cmp = icmp eq i8 %shr, 128
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_both_equal
; CHECK-NEXT: icmp ne i8 %a, 0
define i1 @exact_ashr_ne_both_equal(i8 %a) {
%shr = ashr exact i8 128, %a
%cmp = icmp ne i8 %shr, 128
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_both_equal
; CHECK-NEXT: icmp eq i8 %a, 0
define i1 @exact_lshr_eq_both_equal(i8 %a) {
%shr = lshr exact i8 126, %a
%cmp = icmp eq i8 %shr, 126
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_both_equal
; CHECK-NEXT: icmp ne i8 %a, 0
define i1 @exact_lshr_ne_both_equal(i8 %a) {
%shr = lshr exact i8 126, %a
%cmp = icmp ne i8 %shr, 126
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_opposite_msb
; CHECK-NEXT: ret i1 false
define i1 @exact_ashr_eq_opposite_msb(i8 %a) {
%shr = ashr exact i8 -128, %a
%cmp = icmp eq i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @ashr_eq_opposite_msb
; CHECK-NEXT: ret i1 false
define i1 @ashr_eq_opposite_msb(i8 %a) {
%shr = ashr i8 -128, %a
%cmp = icmp eq i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_opposite_msb
; CHECK-NEXT: icmp eq i8 %a, 7
define i1 @exact_lshr_eq_opposite_msb(i8 %a) {
%shr = lshr exact i8 -128, %a
%cmp = icmp eq i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @lshr_eq_opposite_msb
; CHECK-NEXT: icmp eq i8 %a, 7
define i1 @lshr_eq_opposite_msb(i8 %a) {
%shr = lshr i8 -128, %a
%cmp = icmp eq i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_opposite_msb
; CHECK-NEXT: ret i1 true
define i1 @exact_ashr_ne_opposite_msb(i8 %a) {
%shr = ashr exact i8 -128, %a
%cmp = icmp ne i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @ashr_ne_opposite_msb
; CHECK-NEXT: ret i1 true
define i1 @ashr_ne_opposite_msb(i8 %a) {
%shr = ashr i8 -128, %a
%cmp = icmp ne i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_opposite_msb
; CHECK-NEXT: icmp ne i8 %a, 7
define i1 @exact_lshr_ne_opposite_msb(i8 %a) {
%shr = lshr exact i8 -128, %a
%cmp = icmp ne i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @lshr_ne_opposite_msb
; CHECK-NEXT: icmp ne i8 %a, 7
define i1 @lshr_ne_opposite_msb(i8 %a) {
%shr = lshr i8 -128, %a
%cmp = icmp ne i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_shift_gt
; CHECK-NEXT : ret i1 false
define i1 @exact_ashr_eq_shift_gt(i8 %a) {
%shr = ashr exact i8 -2, %a
%cmp = icmp eq i8 %shr, -8
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_shift_gt
; CHECK-NEXT : ret i1 true
define i1 @exact_ashr_ne_shift_gt(i8 %a) {
%shr = ashr exact i8 -2, %a
%cmp = icmp ne i8 %shr, -8
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq_shift_gt
; CHECK-NEXT : ret i1 false
define i1 @nonexact_ashr_eq_shift_gt(i8 %a) {
%shr = ashr i8 -2, %a
%cmp = icmp eq i8 %shr, -8
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne_shift_gt
; CHECK-NEXT : ret i1 true
define i1 @nonexact_ashr_ne_shift_gt(i8 %a) {
%shr = ashr i8 -2, %a
%cmp = icmp ne i8 %shr, -8
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_shift_gt
; CHECK-NEXT: ret i1 false
define i1 @exact_lshr_eq_shift_gt(i8 %a) {
%shr = lshr exact i8 2, %a
%cmp = icmp eq i8 %shr, 8
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_shift_gt
; CHECK-NEXT: ret i1 true
define i1 @exact_lshr_ne_shift_gt(i8 %a) {
%shr = lshr exact i8 2, %a
%cmp = icmp ne i8 %shr, 8
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq_shift_gt
; CHECK-NEXT : ret i1 false
define i1 @nonexact_lshr_eq_shift_gt(i8 %a) {
%shr = lshr i8 2, %a
%cmp = icmp eq i8 %shr, 8
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne_shift_gt
; CHECK-NEXT : ret i1 true
define i1 @nonexact_lshr_ne_shift_gt(i8 %a) {
%shr = ashr i8 2, %a
%cmp = icmp ne i8 %shr, 8
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq
; CHECK-NEXT: icmp eq i8 %a, 7
define i1 @exact_ashr_eq(i8 %a) {
%shr = ashr exact i8 -128, %a
%cmp = icmp eq i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne
; CHECK-NEXT: icmp ne i8 %a, 7
define i1 @exact_ashr_ne(i8 %a) {
%shr = ashr exact i8 -128, %a
%cmp = icmp ne i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq
; CHECK-NEXT: icmp eq i8 %a, 2
define i1 @exact_lshr_eq(i8 %a) {
%shr = lshr exact i8 4, %a
%cmp = icmp eq i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne
; CHECK-NEXT: icmp ne i8 %a, 2
define i1 @exact_lshr_ne(i8 %a) {
%shr = lshr exact i8 4, %a
%cmp = icmp ne i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq
; CHECK-NEXT: icmp eq i8 %a, 7
define i1 @nonexact_ashr_eq(i8 %a) {
%shr = ashr i8 -128, %a
%cmp = icmp eq i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne
; CHECK-NEXT: icmp ne i8 %a, 7
define i1 @nonexact_ashr_ne(i8 %a) {
%shr = ashr i8 -128, %a
%cmp = icmp ne i8 %shr, -1
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq
; CHECK-NEXT: icmp eq i8 %a, 2
define i1 @nonexact_lshr_eq(i8 %a) {
%shr = lshr i8 4, %a
%cmp = icmp eq i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne
; CHECK-NEXT: icmp ne i8 %a, 2
define i1 @nonexact_lshr_ne(i8 %a) {
%shr = lshr i8 4, %a
%cmp = icmp ne i8 %shr, 1
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_exactdiv
; CHECK-NEXT: icmp eq i8 %a, 4
define i1 @exact_lshr_eq_exactdiv(i8 %a) {
%shr = lshr exact i8 80, %a
%cmp = icmp eq i8 %shr, 5
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_exactdiv
; CHECK-NEXT: icmp ne i8 %a, 4
define i1 @exact_lshr_ne_exactdiv(i8 %a) {
%shr = lshr exact i8 80, %a
%cmp = icmp ne i8 %shr, 5
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq_exactdiv
; CHECK-NEXT: icmp eq i8 %a, 4
define i1 @nonexact_lshr_eq_exactdiv(i8 %a) {
%shr = lshr i8 80, %a
%cmp = icmp eq i8 %shr, 5
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne_exactdiv
; CHECK-NEXT: icmp ne i8 %a, 4
define i1 @nonexact_lshr_ne_exactdiv(i8 %a) {
%shr = lshr i8 80, %a
%cmp = icmp ne i8 %shr, 5
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_exactdiv
; CHECK-NEXT: icmp eq i8 %a, 4
define i1 @exact_ashr_eq_exactdiv(i8 %a) {
%shr = ashr exact i8 -80, %a
%cmp = icmp eq i8 %shr, -5
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_exactdiv
; CHECK-NEXT: icmp ne i8 %a, 4
define i1 @exact_ashr_ne_exactdiv(i8 %a) {
%shr = ashr exact i8 -80, %a
%cmp = icmp ne i8 %shr, -5
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq_exactdiv
; CHECK-NEXT: icmp eq i8 %a, 4
define i1 @nonexact_ashr_eq_exactdiv(i8 %a) {
%shr = ashr i8 -80, %a
%cmp = icmp eq i8 %shr, -5
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne_exactdiv
; CHECK-NEXT: icmp ne i8 %a, 4
define i1 @nonexact_ashr_ne_exactdiv(i8 %a) {
%shr = ashr i8 -80, %a
%cmp = icmp ne i8 %shr, -5
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_noexactdiv
; CHECK-NEXT: ret i1 false
define i1 @exact_lshr_eq_noexactdiv(i8 %a) {
%shr = lshr exact i8 80, %a
%cmp = icmp eq i8 %shr, 31
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_noexactdiv
; CHECK-NEXT: ret i1 true
define i1 @exact_lshr_ne_noexactdiv(i8 %a) {
%shr = lshr exact i8 80, %a
%cmp = icmp ne i8 %shr, 31
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq_noexactdiv
; CHECK-NEXT: ret i1 false
define i1 @nonexact_lshr_eq_noexactdiv(i8 %a) {
%shr = lshr i8 80, %a
%cmp = icmp eq i8 %shr, 31
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne_noexactdiv
; CHECK-NEXT: ret i1 true
define i1 @nonexact_lshr_ne_noexactdiv(i8 %a) {
%shr = lshr i8 80, %a
%cmp = icmp ne i8 %shr, 31
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_noexactdiv
; CHECK-NEXT: ret i1 false
define i1 @exact_ashr_eq_noexactdiv(i8 %a) {
%shr = ashr exact i8 -80, %a
%cmp = icmp eq i8 %shr, -31
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_noexactdiv
; CHECK-NEXT: ret i1 true
define i1 @exact_ashr_ne_noexactdiv(i8 %a) {
%shr = ashr exact i8 -80, %a
%cmp = icmp ne i8 %shr, -31
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq_noexactdiv
; CHECK-NEXT: ret i1 false
define i1 @nonexact_ashr_eq_noexactdiv(i8 %a) {
%shr = ashr i8 -80, %a
%cmp = icmp eq i8 %shr, -31
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne_noexactdiv
; CHECK-NEXT: ret i1 true
define i1 @nonexact_ashr_ne_noexactdiv(i8 %a) {
%shr = ashr i8 -80, %a
%cmp = icmp ne i8 %shr, -31
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_eq_noexactlog
; CHECK-NEXT: ret i1 false
define i1 @exact_lshr_eq_noexactlog(i8 %a) {
%shr = lshr exact i8 90, %a
%cmp = icmp eq i8 %shr, 30
ret i1 %cmp
}
; CHECK-LABEL: @exact_lshr_ne_noexactlog
; CHECK-NEXT: ret i1 true
define i1 @exact_lshr_ne_noexactlog(i8 %a) {
%shr = lshr exact i8 90, %a
%cmp = icmp ne i8 %shr, 30
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_eq_noexactlog
; CHECK-NEXT: ret i1 false
define i1 @nonexact_lshr_eq_noexactlog(i8 %a) {
%shr = lshr i8 90, %a
%cmp = icmp eq i8 %shr, 30
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_lshr_ne_noexactlog
; CHECK-NEXT: ret i1 true
define i1 @nonexact_lshr_ne_noexactlog(i8 %a) {
%shr = lshr i8 90, %a
%cmp = icmp ne i8 %shr, 30
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_eq_noexactlog
; CHECK-NEXT: ret i1 false
define i1 @exact_ashr_eq_noexactlog(i8 %a) {
%shr = ashr exact i8 -90, %a
%cmp = icmp eq i8 %shr, -30
ret i1 %cmp
}
; CHECK-LABEL: @exact_ashr_ne_noexactlog
; CHECK-NEXT: ret i1 true
define i1 @exact_ashr_ne_noexactlog(i8 %a) {
%shr = ashr exact i8 -90, %a
%cmp = icmp ne i8 %shr, -30
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_eq_noexactlog
; CHECK-NEXT: ret i1 false
define i1 @nonexact_ashr_eq_noexactlog(i8 %a) {
%shr = ashr i8 -90, %a
%cmp = icmp eq i8 %shr, -30
ret i1 %cmp
}
; CHECK-LABEL: @nonexact_ashr_ne_noexactlog
; CHECK-NEXT: ret i1 true
define i1 @nonexact_ashr_ne_noexactlog(i8 %a) {
%shr = ashr i8 -90, %a
%cmp = icmp ne i8 %shr, -30
ret i1 %cmp
}
; Don't try to fold the entire body of function @PR20945 into a
; single `ret i1 true` statement.
; If %B is equal to 1, then this function would return false.
; As a consequence, the instruction combiner is not allowed to fold %cmp
; to 'true'. Instead, it should replace %cmp with a simpler comparison
; between %B and 1.
; CHECK-LABEL: @PR20945(
; CHECK: icmp ne i32 %B, 1
define i1 @PR20945(i32 %B) {
%shr = ashr i32 -9, %B
%cmp = icmp ne i32 %shr, -5
ret i1 %cmp
}
; CHECK-LABEL: @PR21222
; CHECK: icmp eq i32 %B, 6
define i1 @PR21222(i32 %B) {
%shr = ashr i32 -93, %B
%cmp = icmp eq i32 %shr, -2
ret i1 %cmp
}