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author | Nick Lewycky <nicholas@mxc.ca> | 2014-05-20 05:13:21 +0000 |
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committer | Nick Lewycky <nicholas@mxc.ca> | 2014-05-20 05:13:21 +0000 |
commit | 4bf804fe0d352ea5a69beb0962d99c333beabd32 (patch) | |
tree | ed07f6733eaf17ab0b165b3d9da063ad389539b7 | |
parent | 956583e98e57bea245137a7833a4b329edd897cf (diff) | |
download | llvm-4bf804fe0d352ea5a69beb0962d99c333beabd32.tar.gz llvm-4bf804fe0d352ea5a69beb0962d99c333beabd32.tar.bz2 llvm-4bf804fe0d352ea5a69beb0962d99c333beabd32.tar.xz |
Teach isKnownNonNull that a nonnull return is not null. Add a test for this case as well as the case of a nonnull attribute (already handled but not tested).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209193 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r-- | lib/Analysis/ValueTracking.cpp | 5 | ||||
-rw-r--r-- | test/Transforms/InstSimplify/compare.ll | 17 |
2 files changed, 22 insertions, 0 deletions
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp index 280f15b509..4f48753578 100644 --- a/lib/Analysis/ValueTracking.cpp +++ b/lib/Analysis/ValueTracking.cpp @@ -16,6 +16,7 @@ #include "llvm/ADT/SmallPtrSet.h" #include "llvm/Analysis/InstructionSimplify.h" #include "llvm/Analysis/MemoryBuiltins.h" +#include "llvm/IR/CallSite.h" #include "llvm/IR/ConstantRange.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" @@ -2073,6 +2074,10 @@ bool llvm::isKnownNonNull(const Value *V, const TargetLibraryInfo *TLI) { if (const GlobalValue *GV = dyn_cast<GlobalValue>(V)) return !GV->hasExternalWeakLinkage(); + if (ImmutableCallSite CS = V) + if (CS.paramHasAttr(0, Attribute::NonNull)) + return true; + // operator new never returns null. if (isOperatorNewLikeFn(V, TLI, /*LookThroughBitCast=*/true)) return true; diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll index 1a62e27dd8..105e244ed8 100644 --- a/test/Transforms/InstSimplify/compare.ll +++ b/test/Transforms/InstSimplify/compare.ll @@ -866,3 +866,20 @@ define i1 @exact_ashr_sgt_false(i32 %a) { ; CHECK-LABEL: @exact_ashr_sgt_false ; CHECK-NEXT: ret i1 false } + +define i1 @nonnull_arg(i32* nonnull %i) { + %cmp = icmp eq i32* %i, null + ret i1 %cmp +; CHECK-LABEL: @nonnull_arg +; CHECK: ret i1 false +} + +declare nonnull i32* @returns_nonnull_helper() +define i1 @returns_nonnull() { + %call = call nonnull i32* @returns_nonnull_helper() + %cmp = icmp eq i32* %call, null + ret i1 %cmp +; CHECK-LABEL: @returns_nonnull +; CHECK: ret i1 false +} + |