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[Instcombine][Tests] Add test for folding select
to cmp with weak inequalities and constants on RHS. Tests has baseline CHECK lines.
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‎llvm/test/Transforms/InstCombine/scmp.ll

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@@ -473,3 +473,4 @@ define i8 @scmp_from_select_eq_and_gt_neg3(i32 %x, i32 %y) {
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%r = select i1 %eq, i8 0, i8 %sel1
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ret i8 %r
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}
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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 %
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; Fold (x < y) ? -1 : zext(x != y) to scmp(x, y)
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define i32 @scmp_x_y_from_lt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_x_y_from_lt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[SEL:%.*]] = call i32 @llvm.scmp.i32.i32(i32 [[X]], i32 [[Y]])
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp ne i32 %x, %y
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%zext = zext i1 %cmp1 to i32
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%cmp2 = icmp slt i32 %x, %y
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%sel = select i1 %cmp2, i32 -1, i32 %zext
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ret i32 %sel
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}
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; Fold (x < y) ? -1 : zext(x > y) to scmp(x, y)
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define i32 @scmp_x_y_from_lt_gt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_x_y_from_lt_gt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[SEL:%.*]] = call i32 @llvm.scmp.i32.i32(i32 [[X]], i32 [[Y]])
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp sgt i32 %x, %y
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%zext = zext i1 %cmp1 to i32
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%cmp2 = icmp slt i32 %x, %y
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%sel = select i1 %cmp2, i32 -1, i32 %zext
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ret i32 %sel
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}
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; Fold (x > y) ? 1 : sext(x != y) to scmp(x, y)
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define i32 @scmp_x_y_from_gt_sext_ne(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_x_y_from_gt_sext_ne(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[SEL:%.*]] = call i32 @llvm.scmp.i32.i32(i32 [[X]], i32 [[Y]])
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp ne i32 %x, %y
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%sext = sext i1 %cmp1 to i32
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%cmp2 = icmp sgt i32 %x, %y
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%sel = select i1 %cmp2, i32 1, i32 %sext
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ret i32 %sel
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}
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; Fold (x > y) ? 1 : sext(x < y) to scmp(x, y)
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define i32 @scmp_x_y_from_gt_sext_lt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_x_y_from_gt_sext_lt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[SEL:%.*]] = call i32 @llvm.scmp.i32.i32(i32 [[X]], i32 [[Y]])
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp slt i32 %x, %y
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%sext = sext i1 %cmp1 to i32
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%cmp2 = icmp sgt i32 %x, %y
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%sel = select i1 %cmp2, i32 1, i32 %sext
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ret i32 %sel
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}
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; Fold (x <= y - 1) ? -1 : zext(x != y) to ucmp(x, y)
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define i32 @ucmp_x_y_from_le_sub_zext_ne(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @ucmp_x_y_from_le_sub_zext_ne(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YM1:%.*]] = add i32 [[Y]], -1
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; CHECK-NEXT: [[CMP1_NOT:%.*]] = icmp ugt i32 [[X]], [[YM1]]
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; CHECK-NEXT: [[NEQ:%.*]] = icmp ne i32 [[X]], [[Y]]
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; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[NEQ]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1_NOT]], i32 [[ZEXT]], i32 -1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%ym1 = sub i32 %y, 1
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%cmp1 = icmp ule i32 %x, %ym1
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%neq = icmp ne i32 %x, %y
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%zext = zext i1 %neq to i32
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%sel = select i1 %cmp1, i32 -1, i32 %zext
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ret i32 %sel
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}
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; Fold (x <= y - 1) ? -1 : zext(x > y) to ucmp(x, y)
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define i32 @ucmp_x_y_from_le_sub_zext_gt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @ucmp_x_y_from_le_sub_zext_gt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YM1:%.*]] = add i32 [[Y]], -1
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; CHECK-NEXT: [[CMP1_NOT:%.*]] = icmp ugt i32 [[X]], [[YM1]]
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; CHECK-NEXT: [[GT:%.*]] = icmp ugt i32 [[X]], [[Y]]
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; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[GT]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1_NOT]], i32 [[ZEXT]], i32 -1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%ym1 = sub i32 %y, 1
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%cmp1 = icmp ule i32 %x, %ym1
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%gt = icmp ugt i32 %x, %y
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%zext = zext i1 %gt to i32
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%sel = select i1 %cmp1, i32 -1, i32 %zext
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ret i32 %sel
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}
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; Fold (x >= y + 1) ? 1 : sext(x != y) to ucmp(x, y)
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define i32 @ucmp_x_y_from_ge_add_sext_ne(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @ucmp_x_y_from_ge_add_sext_ne(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YP1:%.*]] = add i32 [[Y]], 1
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; CHECK-NEXT: [[CMP1_NOT:%.*]] = icmp ult i32 [[X]], [[YP1]]
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; CHECK-NEXT: [[NEQ:%.*]] = icmp ne i32 [[X]], [[Y]]
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; CHECK-NEXT: [[SEXT:%.*]] = sext i1 [[NEQ]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1_NOT]], i32 [[SEXT]], i32 1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%yp1 = add i32 %y, 1
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%cmp1 = icmp uge i32 %x, %yp1
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%neq = icmp ne i32 %x, %y
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%sext = sext i1 %neq to i32
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%sel = select i1 %cmp1, i32 1, i32 %sext
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ret i32 %sel
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}
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; Fold (x >= y + 1) ? 1 : sext(x < y) to ucmp(x, y)
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define i32 @ucmp_x_y_from_ge_add_sext_lt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @ucmp_x_y_from_ge_add_sext_lt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YP1:%.*]] = add i32 [[Y]], 1
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; CHECK-NEXT: [[CMP1_NOT:%.*]] = icmp ult i32 [[X]], [[YP1]]
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; CHECK-NEXT: [[LT:%.*]] = icmp ult i32 [[X]], [[Y]]
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; CHECK-NEXT: [[SEXT:%.*]] = sext i1 [[LT]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1_NOT]], i32 [[SEXT]], i32 1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%yp1 = add i32 %y, 1
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%cmp1 = icmp uge i32 %x, %yp1
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%lt = icmp ult i32 %x, %y
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%sext = sext i1 %lt to i32
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%sel = select i1 %cmp1, i32 1, i32 %sext
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ret i32 %sel
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}
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; Fold (x > y - 1) ? zext(x != y) : -1 to scmp(x, y)
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define i32 @scmp_x_y_from_gt_sub_zext_ne(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_x_y_from_gt_sub_zext_ne(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YM1:%.*]] = add i32 [[Y]], -1
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; CHECK-NEXT: [[CMP1:%.*]] = icmp sgt i32 [[X]], [[YM1]]
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; CHECK-NEXT: [[NE:%.*]] = icmp ne i32 [[X]], [[Y]]
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; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[NE]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i32 [[ZEXT]], i32 -1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%ym1 = sub i32 %y, 1
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%cmp1 = icmp sgt i32 %x, %ym1
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%ne = icmp ne i32 %x, %y
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%zext = zext i1 %ne to i32
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%sel = select i1 %cmp1, i32 %zext, i32 -1
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ret i32 %sel
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}
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; Fold (x > y - 1) ? zext(x > y) : -1 to ucmp(x, y)
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define i32 @ucmp_x_y_from_gt_sub_zext_gt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @ucmp_x_y_from_gt_sub_zext_gt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YM1:%.*]] = add i32 [[Y]], -1
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; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i32 [[X]], [[YM1]]
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; CHECK-NEXT: [[GT:%.*]] = icmp ugt i32 [[X]], [[Y]]
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; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[GT]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i32 [[ZEXT]], i32 -1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%ym1 = sub i32 %y, 1
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%cmp1 = icmp ugt i32 %x, %ym1
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%gt = icmp ugt i32 %x, %y
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%zext = zext i1 %gt to i32
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%sel = select i1 %cmp1, i32 %zext, i32 -1
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ret i32 %sel
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}
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; Fold (x < y + 1) ? sext(x != y) : 1 to scmp(x, y)
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define i32 @scmp_x_y_from_lt_add_sext_ne(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_x_y_from_lt_add_sext_ne(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YP1:%.*]] = add i32 [[Y]], 1
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; CHECK-NEXT: [[CMP1:%.*]] = icmp slt i32 [[X]], [[YP1]]
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; CHECK-NEXT: [[NE:%.*]] = icmp ne i32 [[X]], [[Y]]
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; CHECK-NEXT: [[SEXT:%.*]] = sext i1 [[NE]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i32 [[SEXT]], i32 1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%yp1 = add i32 %y, 1
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%cmp1 = icmp slt i32 %x, %yp1
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%ne = icmp ne i32 %x, %y
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%sext = sext i1 %ne to i32
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%sel = select i1 %cmp1, i32 %sext, i32 1
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ret i32 %sel
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}
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; Fold (x < y + 1) ? sext(x < y) : 1 to ucmp(x, y)
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define i32 @ucmp_x_y_from_lt_add_sext_lt(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @ucmp_x_y_from_lt_add_sext_lt(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[YP1:%.*]] = add i32 [[Y]], 1
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; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i32 [[X]], [[YP1]]
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; CHECK-NEXT: [[LT:%.*]] = icmp ult i32 [[X]], [[Y]]
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; CHECK-NEXT: [[SEXT:%.*]] = sext i1 [[LT]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i32 [[SEXT]], i32 1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%yp1 = add i32 %y, 1
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%cmp1 = icmp ult i32 %x, %yp1
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%lt = icmp ult i32 %x, %y
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%sext = sext i1 %lt to i32
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%sel = select i1 %cmp1, i32 %sext, i32 1
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ret i32 %sel
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}
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; Testing with constants
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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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define i32 @scmp_x_neg_6_sgt_form(i32 %x) {
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; CHECK-LABEL: define i32 @scmp_x_neg_6_sgt_form(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[CMP1:%.*]] = icmp sgt i32 [[X]], -6
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; CHECK-NEXT: [[NE:%.*]] = icmp ne i32 [[X]], -5
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; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[NE]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i32 [[ZEXT]], i32 -1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp sgt i32 %x, -6
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%ne = icmp ne i32 %x, -5
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%zext = zext i1 %ne to i32
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%sel = select i1 %cmp1, i32 %zext, i32 -1
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ret i32 %sel
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}
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define i32 @ucmp_x_5_ult_form(i32 %x) {
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; CHECK-LABEL: define i32 @ucmp_x_5_ult_form(
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; CHECK-SAME: i32 [[X:%.*]]) {
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; CHECK-NEXT: [[CMP1:%.*]] = icmp ult i32 [[X]], 6
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; CHECK-NEXT: [[NE:%.*]] = icmp ne i32 [[X]], 5
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; CHECK-NEXT: [[SEXT:%.*]] = sext i1 [[NE]] to i32
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i32 [[SEXT]], i32 1
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp ult i32 %x, 6
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%ne = icmp ne i32 %x, 5
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%sext = sext i1 %ne to i32
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%sel = select i1 %cmp1, i32 %sext, i32 1
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ret i32 %sel
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}
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; Negative examples
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; (x < y) ? -1 : zext(x == y)
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define i32 @scmp_negative_1(i32 %x, i32 %y) {
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; CHECK-LABEL: define i32 @scmp_negative_1(
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; CHECK-SAME: i32 [[X:%.*]], i32 [[Y:%.*]]) {
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; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[X]], [[Y]]
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; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[CMP1]] to i32
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; CHECK-NEXT: [[CMP2:%.*]] = icmp slt i32 [[X]], [[Y]]
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; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP2]], i32 -1, i32 [[ZEXT]]
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; CHECK-NEXT: ret i32 [[SEL]]
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;
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%cmp1 = icmp eq i32 %x, %y
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%zext = zext i1 %cmp1 to i32
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%cmp2 = icmp slt i32 %x, %y
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%sel = select i1 %cmp2, i32 -1, i32 %zext
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ret i32 %sel
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}
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define i32 @scmp_ne_0(i32 noundef %0) {
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; CHECK-LABEL: define i32 @scmp_ne_0(
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; CHECK-SAME: i32 noundef [[TMP0:%.*]]) {
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; CHECK-NEXT: [[TMP5:%.*]] = icmp ne i32 [[TMP0]], 0
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; CHECK-NEXT: [[TMP3:%.*]] = zext i1 [[TMP5]] to i32
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; CHECK-NEXT: [[TMP4:%.*]] = icmp sgt i32 [[TMP0]], 1
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; CHECK-NEXT: [[TMP2:%.*]] = select i1 [[TMP4]], i32 [[TMP3]], i32 -1
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; CHECK-NEXT: ret i32 [[TMP2]]
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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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