test/Transforms/LoopSimplifyCFG/irreducible_cfg.ll

   1 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
   2 ; REQUIRES: asserts
   3 ; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -loop-simplifycfg -debug-only=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa 2>&1 < %s | FileCheck %s
   4 ; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -passes='require<domtree>,loop(simplify-cfg)' -debug-only=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa 2>&1 < %s | FileCheck %s
   5 ; RUN: opt -S -enable-loop-simplifycfg-term-folding=true -loop-simplifycfg -enable-mssa-loop-dependency=true -verify-memoryssa -debug-only=loop-simplifycfg -verify-loop-info -verify-dom-info -verify-loop-lcssa 2>&1 < %s | FileCheck %s
   6
   7 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:1"
   8
   9 ; This test has irreducible CFG, and RPO may be the following:
  10 ; Header, Dead, Irreducible2, Latch, Irreducible3, Irreducible1.
  11 ; As result, we will process Irreducible2 before its predecessor Irreducible1.
  12 ; The current algorithm gets confused in this case. We may support irreducible
  13 ; CFG in the future.
  14 define void @irreducible_cfg(i1 %cond) {
  15 ; CHECK-LABEL: @irreducible_cfg(
  16 ; CHECK-NEXT:  entry:
  17 ; CHECK-NEXT:    br label [[HEADER:%.*]]
  18 ; CHECK:       header:
  19 ; CHECK-NEXT:    br i1 false, label [[DEAD:%.*]], label [[IRREDUCIBLE1:%.*]]
  20 ; CHECK:       dead:
  21 ; CHECK-NEXT:    br label [[IRREDUCIBLE2:%.*]]
  22 ; CHECK:       irreducible2:
  23 ; CHECK-NEXT:    br i1 [[COND:%.*]], label [[LATCH:%.*]], label [[IRREDUCIBLE3:%.*]]
  24 ; CHECK:       latch:
  25 ; CHECK-NEXT:    br label [[HEADER]]
  26 ; CHECK:       irreducible3:
  27 ; CHECK-NEXT:    br label [[IRREDUCIBLE1]]
  28 ; CHECK:       irreducible1:
  29 ; CHECK-NEXT:    br label [[IRREDUCIBLE2]]
  30 ;
  31 entry:
  32   br label %header
  33
  34 header:                                             ; preds = %latch, %entry
  35   br i1 false, label %dead, label %irreducible1
  36
  37 dead:                                          ; preds = %header
  38   br label %irreducible2
  39
  40 irreducible2:                                             ; preds = %irreducible1, %dead
  41   br i1 %cond, label %latch, label %irreducible3
  42
  43 latch:                                         ; preds = %irreducible2
  44   br label %header
  45
  46 irreducible3:                                           ; preds = %irreducible2
  47   br label %irreducible1
  48
  49 irreducible1:                                          ; preds = %irreducible3, %header
  50   br label %irreducible2
  51 }