Commit Graph

24 Commits

Author SHA1 Message Date
Evgeniy Stepanov 2a066afce5 Fix llvm::removeUnreachableBlocks to handle unreachable loops.
llvm-svn: 177713
2013-03-22 08:43:04 +00:00
Evgeniy Stepanov 00062b4498 [msan] Implement sanitize_memory attribute.
Shadow checks are disabled and memory loads always produce fully initialized
values in functions that don't have a sanitize_memory attribute. Value and
argument shadow is propagated as usual.

This change also updates blacklist behaviour to match the above.

llvm-svn: 176247
2013-02-28 11:25:14 +00:00
Evgeniy Stepanov 6f85ef300d [msan] Mostly disable msan-handle-icmp-exact.
It is way too slow. Change the default option value to 0.
Always do exact shadow propagation for unsigned ICmp with constants, it is
cheap (under 1% cpu time) and required for correctness.

llvm-svn: 173682
2013-01-28 11:42:28 +00:00
Evgeniy Stepanov fac8403249 [msan] Implement exact shadow propagation for relational ICmp.
Only for integers, pointers, and vectors of those. No floats.
Instrumentation seems very heavy, and may need to be replaced
with some approximation in the future.

llvm-svn: 173452
2013-01-25 15:31:10 +00:00
Evgeniy Stepanov c4415591ed [msan] Do not insert check on volatile store.
Volatile bitfields can cause valid stores of uninitialized bits.

llvm-svn: 173153
2013-01-22 12:30:52 +00:00
Evgeniy Stepanov 701d2b861e [msan] Temporarily remove ICmpEQ tests.
They are failing on the bots.

llvm-svn: 172540
2013-01-15 17:12:04 +00:00
Evgeniy Stepanov d14e47b146 [msan] Fix handling of equality comparison of pointer vectors.
Also improve test coveration of the handling of relational comparisons.

llvm-svn: 172539
2013-01-15 16:44:52 +00:00
Peter Collingbourne f7d65c43d0 [msan] Change va_start/va_copy shadow memset alignment to 8.
This fixes va_start/va_copy of a va_list field which happens to not
be laid out at a 16-byte boundary.

Differential Revision: http://llvm-reviews.chandlerc.com/D276

llvm-svn: 172128
2013-01-10 22:36:33 +00:00
Evgeniy Stepanov 5eb5bf8b46 [msan] Raise alignment of origin stores/loads when possible.
Origin alignment is as high as the alignment of the corresponding application
location, but never less than 4.

llvm-svn: 171110
2012-12-26 11:55:09 +00:00
Evgeniy Stepanov f19c086d1e [msan] Fix handling of vectors of pointers.
VectorType::getInteger() can not be used with them, because pointer size
depends on the target.

llvm-svn: 171070
2012-12-25 16:04:38 +00:00
Evgeniy Stepanov ec8371283b [msan] Fix handling of select with vector condition.
llvm-svn: 171069
2012-12-25 14:56:21 +00:00
Evgeniy Stepanov 4fbc0d08bf [msan] Remove unreachable blocks before instrumenting a function.
llvm-svn: 170883
2012-12-21 11:18:49 +00:00
Evgeniy Stepanov d7571cd4bc [msan] Heuristically instrument unknown intrinsics.
This changes adds shadow and origin propagation for unknown intrinsics
by examining the arguments and ModRef behaviour. For now, only 3 classes
of intrinsics are handled:
- those that look like simple SIMD store
- those that look like simple SIMD load
- those that don't have memory effects and look like arithmetic/logic/whatever
  operation on simple types.

llvm-svn: 170530
2012-12-19 11:22:04 +00:00
Evgeniy Stepanov 49175b237d [msan] Origin stores and loads do not need explicit alignment.
Origin address is always 4 byte aligned, and the access type is always i32.

llvm-svn: 170199
2012-12-14 13:43:11 +00:00
Evgeniy Stepanov 4f220d96c5 [msan] Do not store origin for clean values.
Instead of unconditionally storing origin with every application store,
only do this when the shadow of the stored value is != 0.

This change also delays instrumentation of stores until after the walk over
function's instructions, because adding new basic blocks confuses InstVisitor.

We only keep 1 origin value per 4 bytes of application memory. This change
fixes the bug when a store of a single clean byte wiped the origin for the
whole 4-byte area.

Since stores of uninitialized values are relatively uncommon, this change
improves performance of track-origins mode by 5% median and by up to 47% on
specs.

llvm-svn: 169490
2012-12-06 11:41:03 +00:00
Evgeniy Stepanov 8b51bab495 [msan] Instrument bswap intrinsic.
llvm-svn: 169383
2012-12-05 14:39:55 +00:00
Evgeniy Stepanov 474cb3b3b5 [msan] Change linkage type of __msan_track_origins.
LinkOnceODRLinkage globals may be removed in GlobalOpt if not used in the
current module.

llvm-svn: 169377
2012-12-05 12:49:41 +00:00
Evgeniy Stepanov 64bc1ab349 Improve MSan tests.
llvm-svn: 169256
2012-12-04 11:42:05 +00:00
Evgeniy Stepanov 5a16af8638 [msan] Tests for vector manipulation instructions.
llvm-svn: 168997
2012-11-30 12:12:20 +00:00
Evgeniy Stepanov 857d9d2a59 [msan] Propagate shadow through (x<0) and (x>=0) comparisons.
This is a special case of signed relational comparison where result
only depends on the sign of x.

llvm-svn: 168881
2012-11-29 14:25:47 +00:00
Evgeniy Stepanov eeb8b7c391 [msan] Fix shadow & origin store & load alignment.
This change ensures that shadow memory accesses have the same alignment
as corresponding app memory accesses.

llvm-svn: 168880
2012-11-29 14:05:53 +00:00
Evgeniy Stepanov c3b579e5ac [msan] Add a test for r168873.
llvm-svn: 168877
2012-11-29 13:11:09 +00:00
Evgeniy Stepanov 4f9240d7e3 [msan] Update tests (broken in r168873).
llvm-svn: 168874
2012-11-29 12:43:56 +00:00
Evgeniy Stepanov d4bd7b73e3 Initial commit of MemorySanitizer.
Compiler pass only.

llvm-svn: 168866
2012-11-29 09:57:20 +00:00