phi-values-usage.ll
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; RUN: opt -debug-pass=Executions -phi-values -memcpyopt -instcombine -disable-output < %s 2>&1 | FileCheck %s -check-prefix=CHECK -check-prefix=CHECK-MEMCPY
; RUN: opt -debug-pass=Executions -memdep -instcombine -disable-output < %s 2>&1 | FileCheck %s -check-prefix=CHECK
; Check that phi values is not run when it's not already available, and that
; basicaa is not freed after a pass that preserves CFG, as it preserves CFG.
; CHECK: Executing Pass 'Phi Values Analysis'
; CHECK: Executing Pass 'Basic Alias Analysis (stateless AA impl)'
; CHECK: Executing Pass 'Memory Dependence Analysis'
; CHECK-MEMCPY: Executing Pass 'MemCpy Optimization'
; CHECK-MEMCPY-DAG: Freeing Pass 'MemCpy Optimization'
; CHECK-DAG: Freeing Pass 'Phi Values Analysis'
; CHECK-DAG: Freeing Pass 'Memory Dependence Analysis'
; CHECK-MEMCPY-NOT: Freeing Pass 'Basic Alias Analysis (stateless AA impl)'
; CHECK-NOT: Executing Pass 'Phi Values Analysis'
; CHECK-NOT: Executing Pass 'Basic Alias Analysis (stateless AA impl)'
; CHECK: Executing Pass 'Combine redundant instructions'
target datalayout = "p:8:8-n8"
declare void @otherfn([4 x i8]*)
declare i32 @__gxx_personality_v0(...)
declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
@c = external global i8*, align 1
; This function is one where if we didn't free basicaa after memcpyopt then the
; usage of basicaa in instcombine would cause a segfault due to stale phi-values
; results being used.
define void @fn(i8* %this, i64* %ptr) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
entry:
%arr = alloca [4 x i8], align 8
%gep1 = getelementptr inbounds [4 x i8], [4 x i8]* %arr, i64 0, i32 0
br i1 undef, label %then, label %if
if:
br label %then
then:
%phi = phi i64* [ %ptr, %if ], [ null, %entry ]
store i8 1, i8* %gep1, align 8
%load = load i64, i64* %phi, align 8
%gep2 = getelementptr inbounds i8, i8* undef, i64 %load
%gep3 = getelementptr inbounds i8, i8* %gep2, i64 40
invoke i32 undef(i8* undef)
to label %invoke unwind label %lpad
invoke:
unreachable
lpad:
landingpad { i8*, i32 }
catch i8* null
call void @otherfn([4 x i8]* nonnull %arr)
unreachable
}
; When running instcombine after memdep, the basicaa used by instcombine uses
; the phivalues that memdep used. This would then cause a segfault due to
; instcombine deleting a phi whose values had been cached.
define void @fn2() {
entry:
%a = alloca i8, align 1
%0 = load i8*, i8** @c, align 1
%1 = bitcast i8* %0 to i8**
br label %for.cond
for.cond: ; preds = %for.body, %entry
%d.0 = phi i8** [ %1, %entry ], [ null, %for.body ]
br i1 undef, label %for.body, label %for.cond.cleanup
for.body: ; preds = %for.cond
store volatile i8 undef, i8* %a, align 1
br label %for.cond
for.cond.cleanup: ; preds = %for.cond
call void @llvm.lifetime.end.p0i8(i64 1, i8* %a)
%2 = load i8*, i8** %d.0, align 1
store i8* %2, i8** @c, align 1
ret void
}