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[Instcombine][Tests] Add test for folding select
to cmp with constants in non-canonical inequalities
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‎llvm/test/Transforms/InstCombine/select-to-cmp.ll

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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
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; RUN: opt -passes=instcombine -S < %s | FileCheck %s
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; Tests for select to scmp
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define i32 @scmp_x_0_inverted(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp ne i32 [[X]], 0
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i32
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; CHECK-NEXT: [[TMP3:%.*]] = icmp sgt i32 [[X]], -1
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP1]]
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;
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%2 = icmp ne i32 %x, 0
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%3 = zext i1 %2 to i32
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%4 = icmp sgt i32 %x, -1
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%5 = select i1 %4, i32 %3, i32 -1
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ret i32 %5
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}
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; y = -10
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define i32 @scmp_x_0_inverted_const_neg10(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted_const_neg10(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp ne i32 [[X]], -10
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i32
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; CHECK-NEXT: [[TMP3:%.*]] = icmp sgt i32 [[X]], -11
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP1]]
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;
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%1 = icmp ne i32 %x, -10
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%2 = zext i1 %1 to i32
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%3 = icmp sgt i32 %x, -11
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; y = 7 (i8)
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define i8 @scmp_x_0_inverted_i8(i8 %x) {
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; CHECK-LABEL: define i8 @scmp_x_0_inverted_i8(
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; CHECK-SAME: i8 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp ne i8 [[X]], 7
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i8
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; CHECK-NEXT: [[TMP3:%.*]] = icmp sgt i8 [[X]], 6
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i8 [[TMP2]], i8 -1
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; CHECK-NEXT: ret i8 [[TMP1]]
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;
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%1 = icmp ne i8 %x, 7
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%2 = zext i1 %1 to i8
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%3 = icmp sgt i8 %x, 6
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%4 = select i1 %3, i8 %2, i8 -1
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ret i8 %4
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}
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; scmp using ints of two kinds- i32 and i64
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define i32 @scmp_x_0_inverted_i64_neq(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted_i64_neq(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i32 [[X]], 0
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; CHECK-NEXT: [[CMP2:%.*]] = icmp sgt i32 [[X]], -1
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; CHECK-NEXT: [[TMP1:%.*]] = zext i1 [[CMP1]] to i32
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; CHECK-NEXT: [[RET:%.*]] = select i1 [[CMP2]], i32 [[TMP1]], i32 -1
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; CHECK-NEXT: ret i32 [[RET]]
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;
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%x64 = sext i32 %x to i64
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%cmp1 = icmp ne i64 %x64, 0
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%zext = zext i1 %cmp1 to i64
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%cmp2 = icmp sgt i64 %x64, -1
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%sel = select i1 %cmp2, i64 %zext, i64 -1
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%ret = trunc i64 %sel to i32
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ret i32 %ret
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}
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; Same example as previous but with inequality
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define i32 @scmp_x_0_inverted_i64_sgt(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted_i64_sgt(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[CMP1:%.*]] = icmp sgt i32 [[X]], 0
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; CHECK-NEXT: [[CMP2:%.*]] = icmp sgt i32 [[X]], -1
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; CHECK-NEXT: [[TMP1:%.*]] = zext i1 [[CMP1]] to i32
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; CHECK-NEXT: [[RET:%.*]] = select i1 [[CMP2]], i32 [[TMP1]], i32 -1
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; CHECK-NEXT: ret i32 [[RET]]
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;
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%x64 = sext i32 %x to i64
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%cmp1 = icmp sgt i64 %x64, 0
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%zext = zext i1 %cmp1 to i64
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%cmp2 = icmp sgt i64 %x64, -1
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%sel = select i1 %cmp2, i64 %zext, i64 -1
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%ret = trunc i64 %sel to i32
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ret i32 %ret
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}
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; y = -1000
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define i32 @scmp_x_0_inverted_const_neg1000(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted_const_neg1000(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp sgt i32 [[X]], -1000
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i32
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; CHECK-NEXT: [[TMP3:%.*]] = icmp sgt i32 [[X]], -1001
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP1]]
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;
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%1 = icmp sgt i32 %x, -1000
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%2 = zext i1 %1 to i32
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%3 = icmp sgt i32 %x, -1001
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; y = 1729
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define i32 @scmp_x_0_inverted_const_1729_sgt(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted_const_1729_sgt(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp sgt i32 [[X]], 1729
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i32
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; CHECK-NEXT: [[TMP3:%.*]] = icmp sgt i32 [[X]], 1728
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP1]]
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;
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%1 = icmp sgt i32 %x, 1729
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%2 = zext i1 %1 to i32
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%3 = icmp sgt i32 %x, 1728
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; ucmp with 10
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define i32 @ucmp_x_10_inverted(i32 %x) {
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; CHECK-LABEL: define i32 @ucmp_x_10_inverted(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp ne i32 [[X]], 10
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i32
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; CHECK-NEXT: [[TMP3:%.*]] = icmp ugt i32 [[X]], 9
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP1]]
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;
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%1 = icmp ne i32 %x, 10
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%2 = zext i1 %1 to i32
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%3 = icmp ugt i32 %x, 9
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; ucmp with -3, wraps around
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define i32 @ucmp_x_neg1_inverted(i32 %x) {
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; CHECK-LABEL: define i32 @ucmp_x_neg1_inverted(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp ne i32 [[X]], -3
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i32
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; CHECK-NEXT: [[TMP3:%.*]] = icmp ugt i32 [[X]], -4
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i32 [[TMP2]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP1]]
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;
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%1 = icmp ne i32 %x, -3
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%2 = zext i1 %1 to i32
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%3 = icmp ugt i32 %x, -4
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; ucmp with -4, wraps around
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define i8 @ucmp_x_neg4_i8_ugt(i8 %x) {
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; CHECK-LABEL: define i8 @ucmp_x_neg4_i8_ugt(
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; CHECK-SAME: i8 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP4:%.*]] = icmp ugt i8 [[X]], -4
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP4]] to i8
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; CHECK-NEXT: [[TMP3:%.*]] = icmp ugt i8 [[X]], -5
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; CHECK-NEXT: [[TMP1:%.*]] = select i1 [[TMP3]], i8 [[TMP2]], i8 -1
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; CHECK-NEXT: ret i8 [[TMP1]]
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;
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%1 = icmp ugt i8 %x, -4
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%2 = zext i1 %1 to i8
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%3 = icmp ugt i8 %x, -5
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%4 = select i1 %3, i8 %2, i8 -1
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ret i8 %4
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}
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; Negative examples
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; Not scmp due to wrong RHS of the predicate
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define i32 @scmp_ne_0(i32 %0) {
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; CHECK-LABEL: define i32 @scmp_ne_0(
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; CHECK-SAME: i32 [[TMP0:%.*]]) {
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; CHECK-NEXT: [[TMP2:%.*]] = icmp ne i32 [[TMP0]], 0
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; CHECK-NEXT: [[TMP3:%.*]] = zext i1 [[TMP2]] to i32
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; CHECK-NEXT: [[TMP4:%.*]] = icmp sgt i32 [[TMP0]], 1
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; CHECK-NEXT: [[TMP5:%.*]] = select i1 [[TMP4]], i32 [[TMP3]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP5]]
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;
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%2 = icmp ne i32 %0, 0
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%3 = zext i1 %2 to i32
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%4 = icmp sgt i32 %0, 1
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%5 = select i1 %4, i32 %3, i32 -1
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ret i32 %5
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}
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; y = 0 with unsigned compare but RHS wraps
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define i32 @ucmp_x_0_inverted(i32 %x) {
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; CHECK-LABEL: define i32 @ucmp_x_0_inverted(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: ret i32 -1
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;
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%1 = icmp ne i32 %x, 0
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%2 = zext i1 %1 to i32
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%3 = icmp ugt i32 %x, -1
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; Don't fold with INT32_MIN
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define i32 @scmp_x_0_inverted_const_min(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_0_inverted_const_min(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[X]], -2147483648
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; CHECK-NEXT: [[TMP2:%.*]] = zext i1 [[TMP1]] to i32
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; CHECK-NEXT: ret i32 [[TMP2]]
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;
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%1 = icmp ne i32 %x, -2147483648
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%2 = zext i1 %1 to i32
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%3 = icmp sge i32 %x, -2147483648
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}
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; Comparison of i32 with UINT32_MAX should always be -1
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define i32 @ucmp_x_0_inverted_i64_ugt(i32 %x) {
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; CHECK-LABEL: define i32 @ucmp_x_0_inverted_i64_ugt(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: ret i32 -1
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;
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%x64 = zext i32 %x to i64
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%cmp1 = icmp ugt i64 %x64, 0
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%zext = zext i1 %cmp1 to i64
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%cmp2 = icmp ugt i64 %x64, -1
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%sel = select i1 %cmp2, i64 %zext, i64 -1
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%ret = trunc i64 %sel to i32
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ret i32 %ret
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}
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; y = 4294967295 (UINT32_MAX), simply sign extend neq
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define i32 @ucmp_x_const_u32max(i32 %x) {
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; CHECK-LABEL: define i32 @ucmp_x_const_u32max(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[TMP1:%.*]] = icmp ne i32 [[X]], -1
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; CHECK-NEXT: [[TMP2:%.*]] = sext i1 [[TMP1]] to i32
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; CHECK-NEXT: ret i32 [[TMP2]]
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;
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%1 = icmp ugt i32 %x, 4294967295
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%2 = zext i1 %1 to i32
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%3 = icmp ugt i32 %x, 4294967294
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%4 = select i1 %3, i32 %2, i32 -1
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ret i32 %4
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}

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