might be deliberate "one time" leaks, so that leak checkers can find them.
This is a reapply of r160602 with the fix that this time I'm committing the
code I thought I was committing last time; the I->eraseFromParent() goes
*after* the break out of the loop.

llvm-svn: 160664

rdar://11931823.

llvm-svn: 160637

llvm-svn: 160629

llvm-svn: 160621

moved earlier. This fixes some layering issues.

llvm-svn: 160611

llvm-svn: 160603

r160529 that was subsequently reverted. The fix was to not call
GV->eraseFromParent() right before the caller does the same. The existing
testcases already caught this bug if run under valgrind.

llvm-svn: 160602

move the bounds checking pass to the instrumentation folder, where it belongs. I dunno why in the world I dropped it in the Scalar folder in the first place.
No functionality change.

llvm-svn: 160587

GetBestDestForJumpOnUndef() assumes there is at least 1 successor, which isn't
true if the block ends in an indirect branch with no successors. Fix this by
bailing out earlier in this case.

llvm-svn: 160546

[asan] make sure that the crash callbacks do not get merged (Chandler's idea: insert an empty InlineAsm). Change the order in which the new BBs are inserted: the slow path BB is insert between old BBs, the crash BB is inserted at the end. Don't create an empty BB (introduced by recent commits). Update the test. The experimental code that does manual crash callback merge will most likely be deleted later. 

llvm-svn: 160544

llvm-svn: 160532

memory. This makes clang play nice with leak checkers.

llvm-svn: 160529

No functionality change.

llvm-svn: 160501

llvm-svn: 160477

Minor oversight noticed by inspection. Sorry no unit test.

llvm-svn: 160422

Fixes PR13371: indvars pass incorrectly substitutes 'undef' values.

I do not like this fix. It's needed until/unless the meaning of undef
changes. It attempts to be complete according to the IR spec, but I
don't have much confidence in the implementation given the difficulty
testing undefined behavior. Worse, this invalidates some of my
hard-fought work on indvars and LSR to optimize pointer induction
variables. It results benchmark regressions, which I'll track
internally. On x86_64 no LTO I see:

-3% huffbench
-3% 400.perlbench
-8% fhourstones

My only suggestion for recovering is to change the meaning of
undef. If we could trust an arbitrary instruction to produce a some
real value that can be manipulated (e.g. incremented) according to
non-undef rules, then this case could be easily handled with SCEV.

llvm-svn: 160421

llvm-svn: 160387

[asan] more code to merge crash callbacks. Doesn't fully work yet, but allows to hold performance experiments

llvm-svn: 160361

Speculatively fix crashes by code inspection. Can't reproduce them yet.

llvm-svn: 160344

Some units tests crashed on a different platform.

llvm-svn: 160341

This places limits on CollectSubexprs to constrains the number of
reassociation possibilities. It limits the recursion depth and skips
over chains of nested recurrences outside the current loop.

Fixes PR13361. Although underlying SCEV behavior is still potentially bad.

llvm-svn: 160340

llvm-svn: 160325

[asan] a bit more refactoring, addressed some of the style comments from chandlerc, partially implemented crash callback merging (under flag)

llvm-svn: 160290

[asan] refactor instrumentation to allow merging the crash callbacks (not fully implemented yet, no functionality change except the BB order)

llvm-svn: 160284

llvm-svn: 160269

It turns out that ASan relied on the at-the-end block insertion order to
(purely by happenstance) disable some LLVM optimizations, which in turn
start firing when the ordering is made more "normal". These
optimizations in turn merge many of the instrumentation reporting calls
which breaks the return address based error reporting in ASan.

We're looking at several different options for fixing this.

llvm-svn: 160256

This is particularly useful to the backend code generators which try to
process things in the incoming function order.

Also, cleanup some uses of IRBuilder to be a bit simpler and more clear.

llvm-svn: 160254

the move of *Builder classes into the Core library.

No uses of this builder in Clang or DragonEgg I could find.

If there is a desire to have an IR-building-support library that
contains all of these builders, that can be easily added, but currently
it seems likely that these add no real overhead to VMCore.

llvm-svn: 160243

IRBuilder, DIBuilder, etc.

This is the proper layering as MDBuilder can't be used (or implemented)
without the Core Metadata representation.

Patches to Clang and Dragonegg coming up.

llvm-svn: 160237

All SCEV expressions used by LSR formulae must be safe to
expand. i.e. they may not contain UDiv unless we can prove nonzero
denominator.

Fixes PR11356: LSR hoists UDiv.

llvm-svn: 160205

llvm-svn: 160173

  %shr = lshr i64 %key, 3
  %0 = load i64* %val, align 8
  %sub = add i64 %0, -1
  %and = and i64 %sub, %shr
  ret i64 %and

to:
  %shr = lshr i64 %key, 3
  %0 = load i64* %val, align 8
  %sub = add i64 %0, 2305843009213693951
  %and = and i64 %sub, %shr
  ret i64 %and

The demanded bit optimization is actually a pessimization because add -1 would
be codegen'ed as a sub 1. Teach the demanded constant shrinking optimization
to check for negated constant to make sure it is actually reducing the width
of the constant.

rdar://11793464

llvm-svn: 160101

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

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

[tsan] fix compile-time falilure found while building Chromium with tsan (tsan issue #3). A unit test will follow separately.

llvm-svn: 159736

  IntegersSubsetMapping
  - Replaced type of Items field from std::list with std::map. In neares future I'll test it with DenseMap and do the correspond replacement
    if possible.

llvm-svn: 159703

(LLVM optimizers cannot do this optimization by themselves)

llvm-svn: 159668

  IntegersSubsetMapping
  - Replaced type of Items field from std::list with std::map. In neares future I'll test it with DenseMap and do the correspond replacement
    if possible.

llvm-svn: 159659

This reverts commit b2833d9dcba88c6f0520cad760619200adc0442c.

llvm-svn: 159618

llvm-svn: 159546