Commit Graph

49 Commits

Author SHA1 Message Date
Benjamin Kramer 34764fe2e4 MemoryBuiltins: Properly guard ObjectSizeOffsetVisitor against cycles in the IR.
The previous fix only checked for simple cycles, use a set to catch longer
cycles too.

Drop the broken check from the ObjectSizeOffsetEvaluator. The BoundsChecking
pass doesn't have to deal with invalid IR like InstCombine does.

llvm-svn: 162120
2012-08-17 19:26:41 +00:00
Benjamin Kramer 4901f0d2a2 Guard MemoryBuiltins against self-looping GEPs, which can occur in unreachable code due to constant propagation.
Fixes PR13621.

llvm-svn: 162098
2012-08-17 14:16:37 +00:00
Nuno Lopes 85591f899d fix PR13390: do not loop forever with self-referencing self instructions
llvm-svn: 160876
2012-07-27 18:21:15 +00:00
Nuno Lopes 2a4b09c9de teach objectsize about strdup() and strndup()
llvm-svn: 160676
2012-07-24 16:28:13 +00:00
Nuno Lopes 95cc4f3cb5 instcombine: merge the functions that remove dead allocas and dead mallocs/callocs/...
This patch removes ~70 lines in InstCombineLoadStoreAlloca.cpp and makes both functions a bit more aggressive than before :)
In theory, we can be more aggressive when removing an alloca than a malloc, because an alloca pointer should never escape, but we are not taking advantage of this anyway

llvm-svn: 159952
2012-07-09 18:38:20 +00:00
Nuno Lopes fa0dffccee teach instcombine to remove allocated buffers even if there are stores, memcpy/memmove/memset, and objectsize users.
This means we can do cheap DSE for heap memory.
Nothing is done if the pointer excapes or has a load.

The churn in the tests is mostly due to objectsize, since we want to make sure we
don't delete the malloc call before evaluating the objectsize (otherwise it becomes -1/0)

llvm-svn: 159876
2012-07-06 23:09:25 +00:00
Nuno Lopes 55fff83422 refactor the MemoryBuiltin analysis:
- provide more extensive set of functions to detect library allocation functions (e.g., malloc, calloc, strdup, etc)
 - provide an API to compute the size and offset of an object pointed by

Move a few clients (GVN, AA, instcombine, ...) to the new API.
This implementation is a lot more aggressive than each of the custom implementations being replaced.

Patch reviewed by Nick Lewycky and Chandler Carruth, thanks.

llvm-svn: 158919
2012-06-21 15:45:28 +00:00
Nuno Lopes ad40c0a425 revert my previous patches that introduced an additional parameter to the objectsize intrinsic.
After a lot of discussion, we realized it's not the best option for run-time bounds checking

llvm-svn: 157255
2012-05-22 15:25:31 +00:00
Nuno Lopes e2cfd3ce95 objectsize: add a few more tests and fix a bug
llvm-svn: 156625
2012-05-11 18:25:29 +00:00
Nuno Lopes f573030391 objectsize: add support for GEPs with non-constant indexes
add an additional parameter to InstCombiner::EmitGEPOffset() to force it to *not* emit operations with NUW flag

llvm-svn: 156585
2012-05-10 23:17:35 +00:00
Nuno Lopes 7100f463b0 objectsize:
refactor code a bit to enable future changes to support run-time information
add support to compute allocation sizes at run-time if penalty > 1 (e.g., malloc(x), calloc(x, y), and VLAs)

llvm-svn: 156515
2012-05-09 21:30:57 +00:00
Nuno Lopes 01547b3ad2 change the objectsize intrinsic signature: add a 3rd parameter to denote the maximum runtime performance penalty that the user is willing to accept.
This commit only adds the parameter. Code taking advantage of it will follow.

llvm-svn: 156473
2012-05-09 15:52:43 +00:00
Nuno Lopes d4cf35d775 remove calls to calloc if the allocated memory is not used (it was already being done for malloc)
fix a few typos found by Chad in my previous commit

llvm-svn: 156110
2012-05-03 22:08:19 +00:00
Nuno Lopes d2b71e7fa9 add support for calloc to objectsize lowering
llvm-svn: 156102
2012-05-03 21:19:58 +00:00
Chris Lattner 5756c16cdf make the asmparser reject function and type redefinitions. 'Merging' hasn't been
needed since llvm-gcc 3.4 days.

llvm-svn: 133248
2011-06-17 07:06:44 +00:00
Benjamin Kramer 134cde912a Revert 122959, it needs more thought. Add it back to README.txt with additional notes.
llvm-svn: 123030
2011-01-07 20:42:20 +00:00
Benjamin Kramer ae67cc13a9 InstCombine: Turn _chk functions into the "unsafe" variant if length and max langth are equal.
This happens when we take the (non-constant) length from a malloc.

llvm-svn: 122961
2011-01-06 14:22:52 +00:00
Benjamin Kramer 799b011276 InstCombine: If we call llvm.objectsize on a malloc call we can replace it with the size passed to malloc.
llvm-svn: 122959
2011-01-06 13:11:05 +00:00
Benjamin Kramer a76cc117e0 InstCombine: Teach llvm.objectsize folding to look through GEPs.
llvm-svn: 122958
2011-01-06 13:07:49 +00:00
Nick Lewycky fbe8d2803d Fix declarations in a few more tests.
llvm-svn: 101676
2010-04-17 21:29:25 +00:00
Eric Christopher 1f272f7fd8 Verify function prototypes before trying to optimize functions. We also
need TargetData, just return false if we don't have it.

Update testcases accordingly.

Fixes PR6807.

llvm-svn: 101011
2010-04-12 04:48:00 +00:00
Mon P Wang c576ee9040 Reapply address space patch after fixing an issue in MemCopyOptimizer.
Added support for address spaces and added a isVolatile field to memcpy, memmove, and memset,
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)

llvm-svn: 100304
2010-04-04 03:10:48 +00:00
Mon P Wang 999c1b927b Revert r100191 since it breaks objc in clang
llvm-svn: 100199
2010-04-02 18:43:02 +00:00
Mon P Wang a972ab8564 Reapply address space patch after fixing an issue in MemCopyOptimizer.
Added support for address spaces and added a isVolatile field to memcpy, memmove, and memset,
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)

llvm-svn: 100191
2010-04-02 18:04:15 +00:00
Bob Wilson 6f7fd28824 Revert Mon Ping's change 99928, since it broke all the llvm-gcc buildbots.
llvm-svn: 99948
2010-03-30 22:27:04 +00:00
Mon P Wang 7460571381 Added support for address spaces and added a isVolatile field to memcpy, memmove, and memset,
e.g., llvm.memcpy.i32(i8*, i8*, i32, i32) -> llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
A update of langref will occur in a subsequent checkin.

llvm-svn: 99928
2010-03-30 20:55:56 +00:00
Evan Cheng 3f7842232e Fix an incorrect logic causing instcombine to miss some _chk -> non-chk transformations.
llvm-svn: 99263
2010-03-23 06:06:09 +00:00
Evan Cheng 4f2fd2d2be Re-commit 97860 with fix. getMallocAllocatedType may return null.
llvm-svn: 98000
2010-03-08 22:54:36 +00:00
Eric Christopher a7fb58f5f5 Migrate _chk call lowering from SimplifyLibCalls to InstCombine. Stub
out the remainder of the calls that we should lower in some way and
move the tests to the new correct directory. Fix up tests that are now
optimized more than they were before by -instcombine.

llvm-svn: 97875
2010-03-06 10:50:38 +00:00
Eric Christopher d8b43d0e59 Temporarily revert:
Log:
Transform @llvm.objectsize to integer if the argument is a result of malloc of known size.

Modified:
   llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
   llvm/trunk/test/Transforms/InstCombine/objsize.ll

It appears to be causing swb and nightly test failures.

llvm-svn: 97866
2010-03-06 03:11:35 +00:00
Evan Cheng afdc7d3aab Transform @llvm.objectsize to integer if the argument is a result of malloc of known size.
llvm-svn: 97860
2010-03-06 01:01:42 +00:00
Evan Cheng fffdad58ac Instcombine should turn llvm.objectsize of a alloca with static size to an integer.
llvm-svn: 97827
2010-03-05 20:47:23 +00:00
Dan Gohman 882c95605f LLVM instruction syntax doesn't have trailing semicolons.
llvm-svn: 97456
2010-03-01 17:53:15 +00:00
Evan Cheng 3688b8fa68 Instcombine constant folding can normalize gep with negative index to index with large offset. When instcombine objsize checking transformation sees these geps where the offset seemingly point out of bound, it should just return "i don't know" rather than asserting.
llvm-svn: 96825
2010-02-22 23:34:00 +00:00
Eric Christopher 843a4cc43c Fix a problem where we had bitcasted operands that gave us
odd offsets since the bitcasted pointer size and the offset pointer
size are going to be different types for the GEP vs base object.

llvm-svn: 96134
2010-02-13 23:38:01 +00:00
Eric Christopher cccdc13662 Make sure that ConstantExpr offsets also aren't off of extern
symbols.

Thanks to Duncan Sands for the testcase!

llvm-svn: 95877
2010-02-11 17:44:04 +00:00
Eric Christopher 531ea566a6 Add ConstantExpr handling to Intrinsic::objectsize lowering.
Update testcase accordingly now that we can optimize another
section.

llvm-svn: 95846
2010-02-11 01:48:54 +00:00
Eric Christopher 7b7028fd24 Move Intrinsic::objectsize lowering back to InstCombineCalls and
enable constant 0 offset lowering.

llvm-svn: 95691
2010-02-09 21:24:27 +00:00
Eric Christopher ad1aa86276 Pull these back out, they're a little too aggressive and time
consuming for a simple optimization.

llvm-svn: 95671
2010-02-09 17:29:18 +00:00
Eric Christopher 9f85e7eb16 Add a new pass to do llvm.objsize lowering using SCEV.
Initial skeleton and SCEVUnknown lowering implemented,
the rest should come relatively quickly.  Move testcase
to new directory.

Move pass to right before SimplifyLibCalls - which is
moved down a bit so we can take advantage of a few opts.

llvm-svn: 95628
2010-02-09 00:35:38 +00:00
Eric Christopher 04371b4f12 Remove this code for now. I have a better idea and will rewrite with
that in mind.

llvm-svn: 95402
2010-02-05 19:04:06 +00:00
Eric Christopher 107a1fbf61 Temporarily revert this since it appears to have caused a build
failure.

llvm-svn: 95294
2010-02-04 06:41:27 +00:00
Eric Christopher 42fa84a880 Rework constant expr and array handling for objectsize instcombining.
Fix bugs where we would compute out of bounds as in bounds, and where
we couldn't know that the linker could override the size of an array.

Add a few new testcases, change existing testcase to use a private
global array instead of extern.

llvm-svn: 95283
2010-02-04 02:55:34 +00:00
Eric Christopher f12e18db21 If we're dealing with a zero-length array, don't lower to any
particular size, we just don't know what the length is yet.

llvm-svn: 95266
2010-02-03 23:56:07 +00:00
Eric Christopher d86233c118 Recommit this, looks like it wasn't the cause.
llvm-svn: 95165
2010-02-03 00:21:58 +00:00
Eric Christopher e67d01a9a8 Hopefully temporarily revert this.
llvm-svn: 95154
2010-02-02 23:01:31 +00:00
Eric Christopher 4264e7e46f Re-add strcmp and known size object size checking optimization.
Passed bootstrap and nightly test run here.

llvm-svn: 95145
2010-02-02 22:10:43 +00:00
Eric Christopher 5a0e174863 Revert my last couple of patches. They appear to have broken bison.
llvm-svn: 94841
2010-01-29 21:16:24 +00:00
Eric Christopher 997f7ca8c5 Add constant support to object size handling and remove default
lowering. We'll either figure it out, or not and be lowered by
SelectionDAGBuild.

Add test.

llvm-svn: 94775
2010-01-29 01:09:57 +00:00