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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -loop-reduce < %s | FileCheck %s
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
declare void @use(i8 zeroext)
declare void @use_p(ptr)
; nuw needs to be dropped when switching to post-inc comparison.
define i8 @drop_nuw() {
; CHECK-LABEL: @drop_nuw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: call void @use(i8 zeroext [[IV]])
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], 1
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[IV_NEXT]], 0
; CHECK-NEXT: br i1 [[CMP]], label [[EXIT:%.*]], label [[LOOP]]
; CHECK: exit:
; CHECK-NEXT: [[TMP0:%.*]] = add i8 [[IV_NEXT]], -1
; CHECK-NEXT: ret i8 [[TMP0]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ 0, %entry ], [ %iv.next, %loop ]
call void @use(i8 zeroext %iv)
%iv.next = add nuw i8 %iv, 1
%cmp = icmp eq i8 %iv, -1
br i1 %cmp, label %exit, label %loop
exit:
ret i8 %iv
}
; nsw needs to be dropped when switching to post-inc comparison.
define i8 @drop_nsw() {
; CHECK-LABEL: @drop_nsw(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ 127, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: call void @use(i8 zeroext [[IV]])
; CHECK-NEXT: [[IV_NEXT]] = add i8 [[IV]], -1
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[IV_NEXT]], 127
; CHECK-NEXT: br i1 [[CMP]], label [[EXIT:%.*]], label [[LOOP]]
; CHECK: exit:
; CHECK-NEXT: [[TMP0:%.*]] = add i8 [[IV_NEXT]], 1
; CHECK-NEXT: ret i8 [[TMP0]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ 127, %entry ], [ %iv.next, %loop ]
call void @use(i8 zeroext %iv)
%iv.next = add nsw i8 %iv, -1
%cmp = icmp eq i8 %iv, -128
br i1 %cmp, label %exit, label %loop
exit:
ret i8 %iv
}
; Comparison already in post-inc form, no need to drop nuw.
define i8 @already_postinc() {
; CHECK-LABEL: @already_postinc(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i8 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: call void @use(i8 zeroext [[IV]])
; CHECK-NEXT: [[IV_NEXT]] = add nuw i8 [[IV]], 1
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[IV_NEXT]], -1
; CHECK-NEXT: br i1 [[CMP]], label [[EXIT:%.*]], label [[LOOP]]
; CHECK: exit:
; CHECK-NEXT: [[TMP0:%.*]] = add i8 [[IV_NEXT]], -1
; CHECK-NEXT: ret i8 [[TMP0]]
;
entry:
br label %loop
loop:
%iv = phi i8 [ 0, %entry ], [ %iv.next, %loop ]
call void @use(i8 zeroext %iv)
%iv.next = add nuw i8 %iv, 1
%cmp = icmp eq i8 %iv.next, -1
br i1 %cmp, label %exit, label %loop
exit:
ret i8 %iv
}
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