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|
; Test for a subtle bug when computing analyses during inlining and mutating
; the SCC structure. Without care, this can fail to invalidate analyses.
;
; RUN: opt < %s -passes='cgscc(inline,function(verify<domtree>))' -debug-pass-manager -S 2>&1 | FileCheck %s
; First we check that the passes run in the way we expect. Otherwise this test
; may stop testing anything.
;
; CHECK-LABEL: Starting llvm::Module pass manager run.
; CHECK: Running pass: InlinerPass on (test1_f, test1_g, test1_h)
; CHECK: Running analysis: FunctionAnalysisManagerCGSCCProxy on (test1_f, test1_g, test1_h)
; CHECK: Running analysis: DominatorTreeAnalysis on test1_f
; CHECK: Running analysis: DominatorTreeAnalysis on test1_g
; CHECK: Invalidating all non-preserved analyses for: (test1_f)
; CHECK: Invalidating all non-preserved analyses for: test1_f
; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_f
; CHECK: Invalidating analysis: LoopAnalysis on test1_f
; CHECK: Invalidating analysis: BranchProbabilityAnalysis on test1_f
; CHECK: Invalidating analysis: BlockFrequencyAnalysis on test1_f
; CHECK: Invalidating all non-preserved analyses for: (test1_g, test1_h)
; CHECK: Invalidating all non-preserved analyses for: test1_g
; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_g
; CHECK: Invalidating analysis: LoopAnalysis on test1_g
; CHECK: Invalidating analysis: BranchProbabilityAnalysis on test1_g
; CHECK: Invalidating analysis: BlockFrequencyAnalysis on test1_g
; CHECK: Invalidating all non-preserved analyses for: test1_h
; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_h
; CHECK: Invalidating analysis: LoopAnalysis on test1_h
; CHECK: Invalidating analysis: BranchProbabilityAnalysis on test1_h
; CHECK: Invalidating analysis: BlockFrequencyAnalysis on test1_h
; CHECK-NOT: Invalidating analysis:
; CHECK: Starting llvm::Function pass manager run.
; CHECK-NEXT: Running pass: DominatorTreeVerifierPass on test1_g
; CHECK-NEXT: Running analysis: DominatorTreeAnalysis on test1_g
; CHECK-NEXT: Finished llvm::Function pass manager run.
; CHECK-NEXT: Starting llvm::Function pass manager run.
; CHECK-NEXT: Running pass: DominatorTreeVerifierPass on test1_h
; CHECK-NEXT: Running analysis: DominatorTreeAnalysis on test1_h
; CHECK-NEXT: Finished llvm::Function pass manager run.
; CHECK-NOT: Invalidating analysis:
; CHECK: Running pass: DominatorTreeVerifierPass on test1_f
; CHECK-NEXT: Running analysis: DominatorTreeAnalysis on test1_f
; An external function used to control branches.
declare i1 @flag()
; CHECK-LABEL: declare i1 @flag()
; The utility function with interesting control flow that gets inlined below to
; perturb the dominator tree.
define internal void @callee() {
entry:
%ptr = alloca i8
%flag = call i1 @flag()
br i1 %flag, label %then, label %else
then:
store volatile i8 42, i8* %ptr
br label %return
else:
store volatile i8 -42, i8* %ptr
br label %return
return:
ret void
}
; The 'test1_' prefixed functions work to carefully test that incrementally
; reducing an SCC in the inliner cannot accidentially leave stale function
; analysis results due to failing to invalidate them for all the functions.
; The inliner visits this last function. It can't actually break any cycles
; here, but because we visit this function we compute fresh analyses for it.
; These analyses are then invalidated when we inline callee disrupting the
; CFG, and it is important that they be freed.
define void @test1_h() {
; CHECK-LABEL: define void @test1_h()
entry:
call void @test1_g()
; CHECK: call void @test1_g()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
; We visit this function second and here we inline the edge to 'test1_f'
; separating it into its own SCC. The current SCC is now just 'test1_g' and
; 'test1_h'.
define void @test1_g() {
; CHECK-LABEL: define void @test1_g()
entry:
; This edge gets inlined away.
call void @test1_f()
; CHECK-NOT: call void @test1_f()
; CHECK: call void @test1_g()
; We force this edge to survive inlining.
call void @test1_h() noinline
; CHECK: call void @test1_h()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
; We visit this function first in the inliner, and while we inline callee
; perturbing the CFG, we don't inline anything else and the SCC structure
; remains in tact.
define void @test1_f() {
; CHECK-LABEL: define void @test1_f()
entry:
; We force this edge to survive inlining.
call void @test1_g() noinline
; CHECK: call void @test1_g()
; Pull interesting CFG into this function.
call void @callee()
; CHECK-NOT: call void @callee()
ret void
; CHECK: ret void
}
; The 'test2_' prefixed code works to carefully trigger forming an SCC with
; a dominator tree for one of the functions but not the other and without even
; a function analysis manager proxy for the SCC that things get merged into.
; Without proper handling when updating the call graph this will find a stale
; dominator tree.
@test2_global = external global i32, align 4
define void @test2_hoge(i1 (i32*)* %arg) {
; CHECK-LABEL: define void @test2_hoge(
bb:
%tmp2 = call zeroext i1 %arg(i32* @test2_global)
; CHECK: call zeroext i1 %arg(
br label %bb3
bb3:
%tmp5 = call zeroext i1 %arg(i32* @test2_global)
; CHECK: call zeroext i1 %arg(
br i1 %tmp5, label %bb3, label %bb6
bb6:
ret void
}
define zeroext i1 @test2_widget(i32* %arg) {
; CHECK-LABEL: define zeroext i1 @test2_widget(
bb:
%tmp1 = alloca i8, align 1
%tmp2 = alloca i32, align 4
call void @test2_quux()
; CHECK-NOT: call
;
; CHECK: call zeroext i1 @test2_widget(i32* @test2_global)
; CHECK-NEXT: br label %[[NEW_BB:.*]]
;
; CHECK: [[NEW_BB]]:
; CHECK-NEXT: call zeroext i1 @test2_widget(i32* @test2_global)
;
; CHECK: {{.*}}:
call void @test2_hoge.1(i32* %arg)
; CHECK-NEXT: call void @test2_hoge.1(
%tmp4 = call zeroext i1 @test2_barney(i32* %tmp2)
%tmp5 = zext i1 %tmp4 to i32
store i32 %tmp5, i32* %tmp2, align 4
%tmp6 = call zeroext i1 @test2_barney(i32* null)
call void @test2_ham(i8* %tmp1)
; CHECK: call void @test2_ham(
call void @test2_quux()
; CHECK-NOT: call
;
; CHECK: call zeroext i1 @test2_widget(i32* @test2_global)
; CHECK-NEXT: br label %[[NEW_BB:.*]]
;
; CHECK: [[NEW_BB]]:
; CHECK-NEXT: call zeroext i1 @test2_widget(i32* @test2_global)
;
; CHECK: {{.*}}:
ret i1 true
; CHECK-NEXT: ret i1 true
}
define internal void @test2_quux() {
; CHECK-NOT: @test2_quux
bb:
call void @test2_hoge(i1 (i32*)* @test2_widget)
ret void
}
declare void @test2_hoge.1(i32*)
declare zeroext i1 @test2_barney(i32*)
declare void @test2_ham(i8*)
|
