diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp --- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp +++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp @@ -129,6 +129,14 @@ if (isa(V)) return true; + // The inttoptr case works because isNonEscapingLocalObject considers all + // means of converting or equating a pointer to an int (ptrtoint, ptr store + // which could be followed by an integer load, ptr<->int compare) as + // escaping, and objects located at well-known addresses via platform-specific + // means cannot be considered non-escaping local objects. + if (isa(V)) + return true; + return false; } diff --git a/llvm/test/Analysis/BasicAA/noalias-inttoptr.ll b/llvm/test/Analysis/BasicAA/noalias-inttoptr.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Analysis/BasicAA/noalias-inttoptr.ll @@ -0,0 +1,60 @@ +; RUN: opt < %s -basic-aa -aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s +target datalayout = "p:64:64" + +declare void @escape(i8* %ptr) + +; Verify that unescaped noalias parameter does not alias inttoptr +define void @test1(i8* noalias %P, i64 %Q_as_int) { + ; CHECK-LABEL: Function: test1: + ; CHECK: NoAlias: i8* %P, i8* %Q + %Q = inttoptr i64 %Q_as_int to i8* + store i8 0, i8* %P + store i8 1, i8* %Q + ret void +} + +; Verify that unescaped alloca does not alias inttoptr +define void @test2(i64 %Q_as_int) { + ; CHECK-LABEL: Function: test2: + ; CHECK: NoAlias: i8* %P, i8* %Q + %P = alloca i8 + %Q = inttoptr i64 %Q_as_int to i8* + store i8 0, i8* %P + store i8 1, i8* %Q + ret void +} + +; Verify that escaped noalias parameter may alias inttoptr +define void @test3(i8* noalias %P, i64 %Q_as_int) { + ; CHECK-LABEL: Function: test3: + ; CHECK: MayAlias: i8* %P, i8* %Q + call void @escape(i8* %P) + %Q = inttoptr i64 %Q_as_int to i8* + store i8 0, i8* %P + store i8 1, i8* %Q + ret void +} + +; Verify that escaped alloca may alias inttoptr +define void @test4(i64 %Q_as_int) { + ; CHECK-LABEL: Function: test4: + ; CHECK: MayAlias: i8* %P, i8* %Q + %P = alloca i8 + call void @escape(i8* %P) + %Q = inttoptr i64 %Q_as_int to i8* + store i8 0, i8* %P + store i8 1, i8* %Q + ret void +} + + +; Verify that global may alias inttoptr +@G = external global i8 +define void @test5(i64 %Q_as_int) { + ; CHECK-LABEL: Function: test5: + ; CHECK: MayAlias: i8* %Q, i8* @G + %Q = inttoptr i64 %Q_as_int to i8* + store i8 0, i8* @G + store i8 1, i8* %Q + ret void +}