diff options
Diffstat (limited to 'test/Analysis/CFLAliasAnalysis/branch-alias.ll')
-rw-r--r-- | test/Analysis/CFLAliasAnalysis/branch-alias.ll | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/test/Analysis/CFLAliasAnalysis/branch-alias.ll b/test/Analysis/CFLAliasAnalysis/branch-alias.ll new file mode 100644 index 0000000..8307462 --- /dev/null +++ b/test/Analysis/CFLAliasAnalysis/branch-alias.ll @@ -0,0 +1,73 @@ +; Makes sure that we give up on some pathological cases with inttoptr/ptrtoint +; +; @ptr_test was generated from the following C code: +; void ptr_test() { +; int* A; +; unsigned long RefCopy = 0; +; for (int i = 0; i < 8*sizeof(&A); ++i) { +; if ((unsigned long)&A & (1UL << i)) +; RefCopy |= 1UL << i; +; } +; +; int** AliasA1 = (int**)RefCopy; +; int* ShouldAliasA = *AliasA1; +; } + +; RUN: opt < %s -cfl-aa -aa-eval -print-may-aliases -disable-output 2>&1 | FileCheck %s + +; CHECK: Function: ptr_test +define void @ptr_test() #0 { + ; CHECK: MayAlias: i32** %A, i32** %ShouldAliasA + ; CHECK-NOT: %AliasA1 +entry: + %A = alloca i32*, align 8 + %RefCopy = alloca i64, align 8 + %i = alloca i32, align 4 + %AliasA1 = alloca i32**, align 8 + %ShouldAliasA = alloca i32*, align 8 + store i64 0, i64* %RefCopy, align 8 + store i32 0, i32* %i, align 4 + br label %for.cond + +for.cond: ; preds = %for.inc, %entry + %0 = load i32, i32* %i, align 4 + %conv = sext i32 %0 to i64 + %cmp = icmp ult i64 %conv, 64 + br i1 %cmp, label %for.body, label %for.end + +for.body: ; preds = %for.cond + %1 = ptrtoint i32** %A to i64 + %2 = load i32, i32* %i, align 4 + %sh_prom = zext i32 %2 to i64 + %shl = shl i64 1, %sh_prom + %and = and i64 %1, %shl + %tobool = icmp ne i64 %and, 0 + br i1 %tobool, label %if.then, label %if.end + +if.then: ; preds = %for.body + %3 = load i32, i32* %i, align 4 + %sh_prom2 = zext i32 %3 to i64 + %shl3 = shl i64 1, %sh_prom2 + %4 = load i64, i64* %RefCopy, align 8 + %or = or i64 %4, %shl3 + store i64 %or, i64* %RefCopy, align 8 + br label %if.end + +if.end: ; preds = %if.then, %for.body + br label %for.inc + +for.inc: ; preds = %if.end + %5 = load i32, i32* %i, align 4 + %inc = add nsw i32 %5, 1 + store i32 %inc, i32* %i, align 4 + br label %for.cond + +for.end: ; preds = %for.cond + %6 = load i64, i64* %RefCopy, align 8 + %7 = inttoptr i64 %6 to i32** + store i32** %7, i32*** %AliasA1, align 8 + %8 = load i32**, i32*** %AliasA1, align 8 + %9 = load i32*, i32** %8, align 8 + store i32* %9, i32** %ShouldAliasA, align 8 + ret void +} |