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Diffstat (limited to 'llvm/test/Transforms/Inline/cgscc-incremental-invalidate.ll')
| -rw-r--r-- | llvm/test/Transforms/Inline/cgscc-incremental-invalidate.ll | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/llvm/test/Transforms/Inline/cgscc-incremental-invalidate.ll b/llvm/test/Transforms/Inline/cgscc-incremental-invalidate.ll new file mode 100644 index 00000000000..7c6d0fc04ce --- /dev/null +++ b/llvm/test/Transforms/Inline/cgscc-incremental-invalidate.ll @@ -0,0 +1,111 @@ +; 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_h, test1_g, test1_f) +; CHECK: Running analysis: FunctionAnalysisManagerCGSCCProxy on (test1_h, test1_g, test1_f) +; CHECK: Running analysis: DominatorTreeAnalysis on test1_f +; CHECK: Running analysis: DominatorTreeAnalysis on test1_g +; CHECK: Invalidating all non-preserved analyses for: (test1_h, test1_g, test1_f) +; CHECK: Invalidating all non-preserved analyses for: test1_h +; CHECK-NOT: Invalidating anaylsis: +; CHECK: Invalidating all non-preserved analyses for: test1_g +; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_g +; CHECK: Invalidating all non-preserved analyses for: test1_f +; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_f +; CHECK: Running analysis: DominatorTreeAnalysis on test1_h +; CHECK: Invalidating all non-preserved analyses for: (test1_h, test1_g) +; CHECK: Invalidating all non-preserved analyses for: test1_h +; CHECK: Invalidating analysis: DominatorTreeAnalysis on test1_h + +; 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. + +; 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 +} + +; Next we visit this function 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 +} + +; Finally 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 +} |
