llvm/test/Transforms/SCCP/ipsccp-preserve-pdt.ll

; RUN: opt -passes="ipsccp<func-spec>,print<postdomtree>" -force-specialization -funcspec-max-iters=2 -funcspec-max-clones=1 -funcspec-for-literal-constant=true -S < %s 2>&1 | FileCheck %s

; REQUIRES: asserts

; This test case is trying to validate that the postdomtree is preserved
; correctly by the ipsccp pass. A tricky bug was introduced in commit
; 1b1232047e83b69561 when PDT would be fetched using getCachedAnalysis in order
; to setup a DomTreeUpdater (to update the PDT during transformation in order
; to preserve the analysis). But given that commit the PDT could end up being
; required and calculated via BlockFrequency analysis. So the problem was that
; when setting up the DomTreeUpdater we used a nullptr in case PDT wasn't
; cached at the beginning of IPSCCP, to indicate that no updates were needed
; for PDT. But then the PDT was calculated, given the input IR, and preserved
; using the non-updated state (as the DTU wasn't configured for updating the
; PDT).

; CHECK-NOT: <badref>
; CHECK: Inorder PostDominator Tree: DFSNumbers invalid: 0 slow queries.
; CHECK-NEXT:  [1]  <<exit node>> {4294967295,4294967295} [0]
; CHECK-NEXT:    [2] %for.body {4294967295,4294967295} [1]
; CHECK-NEXT:    [2] %if.end4 {4294967295,4294967295} [1]
; CHECK-NEXT:      [3] %entry {4294967295,4294967295} [2]
; CHECK-NEXT:    [2] %for.body37 {4294967295,4294967295} [1]
; CHECK-NEXT:      [3] %for.cond34 {4294967295,4294967295} [2]
; CHECK-NEXT:        [4] %for.cond16 {4294967295,4294967295} [3]
; CHECK-NEXT: Roots: %for.body %for.body37
; CHECK-NEXT: PostDominatorTree for function: bar
; CHECK-NOT: <badref>

declare hidden i1 @compare(ptr) align 2
declare hidden { i8, ptr } @getType(ptr) align 2

define internal void @foo(ptr %TLI, ptr %DL, ptr %Ty, ptr %ValueVTs, ptr %Offsets, i64 %StartingOffset, i1 %arg) {
entry:
  %VT = alloca i64, align 8
  br i1 false, label %if.then, label %if.end4

if.then:                                          ; preds = %entry
  ret void

if.end4:                                          ; preds = %entry
  %cmp = call zeroext i1 @compare(ptr undef)
  br i1 %cmp, label %for.body, label %for.cond16

for.body:                                         ; preds = %if.end4
  %add13 = add i64 %StartingOffset, undef
  call void @foo(ptr %TLI, ptr %DL, ptr undef, ptr %ValueVTs, ptr %Offsets, i64 %add13)
  unreachable

for.cond16:                                       ; preds = %for.cond34, %if.end4
  %call27 = call { i8, ptr } @getType(ptr %VT)
  br label %for.cond34

for.cond34:                                       ; preds = %for.body37, %for.cond16
  br i1 %arg, label %for.body37, label %for.cond16

for.body37:                                       ; preds = %for.cond34
  %tobool39 = icmp ne ptr %Offsets, null
  br label %for.cond34
}

define hidden { ptr, i32 } @bar(ptr %this) {
entry:
  %Offsets = alloca i64, align 8
  %cmp26 = call zeroext i1 @compare(ptr undef)
  br i1 %cmp26, label %for.body28, label %for.cond.cleanup27

for.cond.cleanup27:                               ; preds = %entry
  ret { ptr, i32 } undef

for.body28:                                       ; preds = %entry
  %call33 = call zeroext i1 @compare(ptr undef)
  br i1 %call33, label %if.then34, label %if.end106

if.then34:                                        ; preds = %for.body28
  call void @foo(ptr %this, ptr undef, ptr undef, ptr undef, ptr null, i64 0)
  unreachable

if.end106:                                        ; preds = %for.body28
  call void @foo(ptr %this, ptr undef, ptr undef, ptr undef, ptr %Offsets, i64 0)
  unreachable
}