Commit Graph

208 Commits

Author SHA1 Message Date
Kostya Serebryany 0b458286e1 Don't speculate loads under ThreadSanitizer
Summary:
Don't speculate loads under ThreadSanitizer.
This fixes https://code.google.com/p/thread-sanitizer/issues/detail?id=40
Also discussed here: http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-November/067929.html

Reviewers: chandlerc

Reviewed By: chandlerc

CC: llvm-commits, dvyukov

Differential Revision: http://llvm-reviews.chandlerc.com/D2227

llvm-svn: 195324
2013-11-21 07:29:28 +00:00
Craig Topper ef9e993eaa Remove x86_sse42_crc32_64_8 intrinsic. It has no functional difference from x86_sse42_crc32_32_8 and was not mapped to a clang builtin. I'm not even sure why this form of the instruction is even called out explicitly in the docs. Also add AutoUpgrade support to convert it into the other intrinsic with appropriate trunc and zext.
llvm-svn: 192672
2013-10-15 05:20:47 +00:00
Benjamin Kramer fd4777c046 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.

llvm-svn: 191310
2013-09-24 16:37:51 +00:00
Matt Arsenault 74742a1bb0 Fix assert with GEP ptr vector indexing structs
Also fix it calculating the wrong value. The struct index
is not a ConstantInt, so it was being interpreted as an array
index.

llvm-svn: 188713
2013-08-19 21:43:16 +00:00
Matt Arsenault f55e5e7954 Teach ValueTracking about address spaces
llvm-svn: 188140
2013-08-10 17:34:08 +00:00
David Majnemer b7d5409ad2 isKnownToBeAPowerOfTwo: Strengthen isKnownToBeAPowerOfTwo's analysis on add instructions
Call into ComputeMaskedBits to figure out which bits are set on both add
operands and determine if the value is a power-of-two-or-zero or not.

llvm-svn: 187445
2013-07-30 21:01:36 +00:00
Craig Topper 2cd5ff8003 Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector size.
llvm-svn: 186098
2013-07-11 16:22:38 +00:00
David Majnemer a92b3c914e ValueTracking: Fix bugs in isKnownToBeAPowerOfTwo
(add nsw x, (and x, y)) isn't a power of two if x is zero, it's zero
(add nsw x, (xor x, y)) isn't a power of two if y has bits set that aren't set in x

llvm-svn: 185954
2013-07-09 18:11:10 +00:00
David Majnemer c13678a24f isKnownToBeAPowerOfTwo: Fix a typo in a comment
llvm-svn: 185748
2013-07-06 02:24:59 +00:00
David Majnemer 7a69d2c06a ValueTracking: Teach isKnownToBeAPowerOfTwo about (ADD X, (XOR X, Y)) where X is a power of two
This allows us to simplify urem instructions involving the add+xor to
turn into simpler math.

llvm-svn: 185272
2013-06-29 23:44:53 +00:00
Michael J. Spencer df1ecbd734 Replace Count{Leading,Trailing}Zeros_{32,64} with count{Leading,Trailing}Zeros.
llvm-svn: 182680
2013-05-24 22:23:49 +00:00
David Majnemer beab5678a3 isKnownToBeAPowerOfTwo: (X & Y) + Y is a power of 2 or zero if y is also.
This is useful if something that looks like (x & (1 << y)) ? 64 : 32 is
the divisor in a modulo operation.

llvm-svn: 182200
2013-05-18 19:30:37 +00:00
Manman Ren 1217112d11 Check whether a pointer is non-null (isKnownNonNull) in isKnownNonZero.
This handles the case where we have an inbounds GEP with alloca as the pointer.
This fixes the regression in PR12750 and rdar://13286434.
Note that we can also fix this by handling some GEP cases in isKnownNonNull.

llvm-svn: 177321
2013-03-18 21:23:25 +00:00
Jakub Staszak b7129f2148 Use dyn_cast instead of isa && cast. No functionality change.
llvm-svn: 176537
2013-03-06 00:16:16 +00:00
Dan Gohman 1b0f79de0a Move isKnownNonNull out of AliasAnalysis.h and into ValueTracking.cpp since
it isn't really an AliasAnalysis concept, and ValueTracking has similar things
that it could plausibly share code with some day.

llvm-svn: 174027
2013-01-31 02:40:59 +00:00
Dan Gohman 20a2ae9df5 Change GetPointerBaseWithConstantOffset's DataLayout argument from a
reference to a pointer, so that it can handle the case where DataLayout
is not available and behave conservatively.

llvm-svn: 174024
2013-01-31 02:00:45 +00:00
Dmitri Gribenko 226fea5bd6 Remove redundant 'llvm::' qualifications
llvm-svn: 172358
2013-01-13 16:01:15 +00:00
Chandler Carruth 9fb823bbd4 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

llvm-svn: 171366
2013-01-02 11:36:10 +00:00
Nuno Lopes 368c4d0e1b reimplement GetPointerBaseWithConstantOffset().
The new code is an improved copy of the code I deleted from Analysis/Loads.cpp.
One less compute-constant-gep-offset implementation. yay :)

llvm-svn: 171326
2012-12-31 20:48:35 +00:00
Craig Topper 1bef2c859f Remove trailing whitespace.
llvm-svn: 170991
2012-12-22 19:15:35 +00:00
Nadav Rotem 11350aafb4 Fix a bug that was found by building clang with -fsanitize.
I introduced it in r166785. PR14291.

If TD is unavailable use getScalarSizeInBits, but don't optimize
pointers or vectors of pointers.

llvm-svn: 170586
2012-12-19 20:47:04 +00:00
Nadav Rotem aa3e2a907e Fix a crash in ValueTracking on vectors of pointers.
llvm-svn: 170240
2012-12-14 20:43:49 +00:00
Rafael Espindola 319f74cd11 Rename isPowerOfTwo to isKnownToBeAPowerOfTwo.
In a previous thread it was pointed out that isPowerOfTwo is not a very precise
name since it can return false for powers of two if it is unable to show that
they are powers of two.

llvm-svn: 170093
2012-12-13 03:37:24 +00:00
Rafael Espindola e40238069e The TargetData is not used for the isPowerOfTwo determination. It has never
been used in the first place.  It simply was passed to the function and to the
recursive invocations.  Simply drop the parameter and update the callers for the
new signature.

Patch by Saleem Abdulrasool!

llvm-svn: 169988
2012-12-12 16:52:40 +00:00
Chandler Carruth 80d3e56c73 Add support to ValueTracking for determining that a pointer is non-null
by virtue of inbounds GEPs that preclude a null pointer.

This is a very common pattern in the code generated by std::vector and
other standard library routines which use allocators that test for null
pervasively. This is one step closer to teaching Clang+LLVM to be able
to produce an empty function for:

  void f() {
    std::vector<int> v;
    v.push_back(1);
    v.push_back(2);
    v.push_back(3);
    v.push_back(4);
  }

Which is related to getting them to completely fold SmallVector
push_back sequences into constants when inlining and other optimizations
make that a possibility.

llvm-svn: 169573
2012-12-07 02:08:58 +00:00