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| author | Benjamin Kramer <benny.kra@googlemail.com> | 2013-09-24 16:37:51 +0000 |
|---|---|---|
| committer | Benjamin Kramer <benny.kra@googlemail.com> | 2013-09-24 16:37:51 +0000 |
| commit | 6629210aaf9d2e4fcbecc80b35f72108304da4b4 (patch) | |
| tree | 9e5c76565a5c82aaaabbee0fab814c018ca838d2 /lib/Analysis/MemoryBuiltins.cpp | |
| parent | d721520e4c5d8ad71310a34727a567c3d74e7c08 (diff) | |
| download | llvm-6629210aaf9d2e4fcbecc80b35f72108304da4b4.tar.gz llvm-6629210aaf9d2e4fcbecc80b35f72108304da4b4.tar.bz2 llvm-6629210aaf9d2e4fcbecc80b35f72108304da4b4.tar.xz | |
Teach MemoryBuiltins and InstructionSimplify that operator new never returns NULL.
This is safe per C++11 18.6.1.1p3: [operator new returns] a non-null pointer to
suitably aligned storage (3.7.4), or else throw a bad_alloc exception. This
requirement is binding on a replacement version of this function.
Brings us a tiny bit closer to eliminating more vector push_backs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191310 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Analysis/MemoryBuiltins.cpp')
| -rw-r--r-- | lib/Analysis/MemoryBuiltins.cpp | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp index 0f0a1c98d0..2ec2aec4aa 100644 --- a/lib/Analysis/MemoryBuiltins.cpp +++ b/lib/Analysis/MemoryBuiltins.cpp @@ -35,6 +35,7 @@ enum AllocType { CallocLike = 1<<1, // allocates + bzero ReallocLike = 1<<2, // reallocates StrDupLike = 1<<3, + OpNewLike = MallocLike | (1<<4), // allocates; never returns null AllocLike = MallocLike | CallocLike | StrDupLike, AnyAlloc = MallocLike | CallocLike | ReallocLike | StrDupLike }; @@ -52,13 +53,13 @@ struct AllocFnsTy { static const AllocFnsTy AllocationFnData[] = { {LibFunc::malloc, MallocLike, 1, 0, -1}, {LibFunc::valloc, MallocLike, 1, 0, -1}, - {LibFunc::Znwj, MallocLike, 1, 0, -1}, // new(unsigned int) + {LibFunc::Znwj, OpNewLike, 1, 0, -1}, // new(unsigned int) {LibFunc::ZnwjRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new(unsigned int, nothrow) - {LibFunc::Znwm, MallocLike, 1, 0, -1}, // new(unsigned long) + {LibFunc::Znwm, OpNewLike, 1, 0, -1}, // new(unsigned long) {LibFunc::ZnwmRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new(unsigned long, nothrow) - {LibFunc::Znaj, MallocLike, 1, 0, -1}, // new[](unsigned int) + {LibFunc::Znaj, OpNewLike, 1, 0, -1}, // new[](unsigned int) {LibFunc::ZnajRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new[](unsigned int, nothrow) - {LibFunc::Znam, MallocLike, 1, 0, -1}, // new[](unsigned long) + {LibFunc::Znam, OpNewLike, 1, 0, -1}, // new[](unsigned long) {LibFunc::ZnamRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new[](unsigned long, nothrow) {LibFunc::posix_memalign, MallocLike, 3, 2, -1}, {LibFunc::calloc, CallocLike, 2, 0, 1}, @@ -189,6 +190,13 @@ bool llvm::isReallocLikeFn(const Value *V, const TargetLibraryInfo *TLI, return getAllocationData(V, ReallocLike, TLI, LookThroughBitCast); } +/// \brief Tests if a value is a call or invoke to a library function that +/// allocates memory and never returns null (such as operator new). +bool llvm::isOperatorNewLikeFn(const Value *V, const TargetLibraryInfo *TLI, + bool LookThroughBitCast) { + return getAllocationData(V, OpNewLike, TLI, LookThroughBitCast); +} + /// extractMallocCall - Returns the corresponding CallInst if the instruction /// is a malloc call. Since CallInst::CreateMalloc() only creates calls, we /// ignore InvokeInst here. |