Commit Graph

383 Commits

Author SHA1 Message Date
David L. Jones 32028c8f08 [Analysis] Add LibFunc_ prefix to enums in TargetLibraryInfo. (NFC)
Summary:
The LibFunc::Func enum holds enumerators named for libc functions.
Unfortunately, there are real situations, including libc implementations, where
function names are actually macros (musl uses "#define fopen64 fopen", for
example; any other transitively visible macro would have similar effects).

Strictly speaking, a conforming C++ Standard Library should provide any such
macros as functions instead (via <cstdio>). However, there are some "library"
functions which are not part of the standard, and thus not subject to this
rule (fopen64, for example). So, in order to be both portable and consistent,
the enum should not use the bare function names.

The old enum naming used a namespace LibFunc and an enum Func, with bare
enumerators. This patch changes LibFunc to be an enum with enumerators prefixed
with "LibFFunc_". (Unfortunately, a scoped enum is not sufficient to override
macros.)

There are additional changes required in clang.

Reviewers: rsmith

Subscribers: mehdi_amini, mzolotukhin, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D28476

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292848 91177308-0d34-0410-b5e6-96231b3b80d8
2017-01-23 23:16:46 +00:00
Adrian Prantl f53a7ab5bb Refactor the DIExpression fragment query interface (NFC)
... so it becomes available to DIExpressionCursor.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290322 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-22 05:27:12 +00:00
Daniel Jasper 8de3a54f07 Revert @llvm.assume with operator bundles (r289755-r289757)
This creates non-linear behavior in the inliner (see more details in
r289755's commit thread).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@290086 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-19 08:22:17 +00:00
Hal Finkel bffeba468d Remove the AssumptionCache
After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is more computationally efficient, and also we need much less
code...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289756 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-15 03:02:15 +00:00
Adrian Prantl 460dd60c1a [DIExpression] Introduce a dedicated DW_OP_LLVM_fragment operation
so we can stop using DW_OP_bit_piece with the wrong semantics.

The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html

The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.

Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.

Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288683 91177308-0d34-0410-b5e6-96231b3b80d8
2016-12-05 18:04:47 +00:00
Michael Zolotukhin 3a7f010bf7 [LoopSimplify] Preserve LCSSA when removing edges from unreachable blocks.
This fixes PR30454.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287379 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-18 21:01:12 +00:00
Florian Hahn 8a56643640 [simplifycfg][loop-simplify] Preserve loop metadata in 2 transformations.
insertUniqueBackedgeBlock in lib/Transforms/Utils/LoopSimplify.cpp now
propagates existing llvm.loop metadata to newly the added backedge.

llvm::TryToSimplifyUncondBranchFromEmptyBlock in lib/Transforms/Utils/Local.cpp
now propagates existing llvm.loop metadata to the branch instructions in the
predecessor blocks of the empty block that is removed.

Differential Revision: https://reviews.llvm.org/D26495


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287341 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-18 13:12:07 +00:00
Kuba Brecka d84b0f9851 [tsan] Add support for C++ exceptions into TSan (call __tsan_func_exit during unwinding), LLVM part
This adds support for TSan C++ exception handling, where we need to add extra calls to __tsan_func_exit when a function is exitted via exception mechanisms. Otherwise the shadow stack gets corrupted (leaked). This patch moves and enhances the existing implementation of EscapeEnumerator that finds all possible function exit points, and adds extra EH cleanup blocks where needed.

Differential Revision: https://reviews.llvm.org/D26177



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286893 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-14 21:41:13 +00:00
Eli Friedman a7bfb15b26 DCE math library calls with a constant operand.
On platforms which use -fmath-errno, math libcalls without any uses
require some extra checks to figure out if they are actually dead.

Fixes https://llvm.org/bugs/show_bug.cgi?id=30464 .

Differential Revision: https://reviews.llvm.org/D25970



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285857 91177308-0d34-0410-b5e6-96231b3b80d8
2016-11-02 20:48:11 +00:00
Reid Kleckner a02ae2b916 [DebugInfo] Add comments to phi dbg.value tracking code, NFC
LLVM developers might be surprised to learn that there are blocks
without valid insertion points (catchswitch), so it seems worth calling
that out explicitly.  Also add a FIXME about what we should really be
doing if we ever need to make optimized Windows EH code debuggable.

While I'm here, make auto usage more consistent with LLVM standards and
avoid an unecessary call to insertBefore.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282521 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-27 18:45:31 +00:00
Keith Walker 523c933b4c Reapplying r281895 (and follow-up r281964) after fixing pr30468.
The additional fix is:

When adding debug information to a lowered phi node in mem2reg
check that we have a valid insertion point after the phi for adding
the debug information.

This change addresses the issue in pr30468 where a lowered phi was
added before a catchswitch and no debug information should be added
after the phi in this case.

Differential Revision: https://reviews.llvm.org/D24797



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282155 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-22 14:13:25 +00:00
Hans Wennborg a613eb13a3 Revert r281895 "Add @llvm.dbg.value entries for the phi node created by -mem2reg"
(And follow-up r281964.)

It caused PR30468.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282077 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-21 15:55:53 +00:00
Keith Walker 4aaf90e08e Make llvm::ConvertDebugDeclareToDebugValue() be a void function (NFC)
The routines llvm::ConvertDebugDeclareToDebugValue() always returned
a true value which was never checked at the call site; change the
function return type to void.

This NFC cleanup was approved in the review https://reviews.llvm.org/D23715


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281964 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-20 10:36:17 +00:00
Keith Walker 383922dd5b Add @llvm.dbg.value entries for the phi node created by -mem2reg
When phi nodes are created in the -mem2reg phase, the @llvm.dbg.declare
entries are converted to @llvm.dbg.value entries at the place where the
store instructions existed. However no entry is created to describe
the resulting value of the phi node.

The effect of this is especially noticeable in for loops which have a
constant for the intial value; the loop control variable's location
would be described as the intial constant value in the loop body once
the -mem2reg optimization phase was run.

This change adds the creation of the @llvm.dbg.value entries to describe
variables whose location is the result of a phi node created in -mem2reg.

Also when the phi node is finally lowered to a machine instruction it
is important that the lowered "load" instruction is placed before the
associated DEBUG_VALUE entry describing the value loaded.

Differential Revision: https://reviews.llvm.org/D23715


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281895 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-19 09:49:30 +00:00
Matt Arsenault 21409dbcdc Fix misleading comment for getOrEnforceKnownAlignment
It does not return 0 to indicate failure, and returns the known
alignment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281350 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-13 16:39:43 +00:00
Dehao Chen 035ff49cd1 revert r280427
Refactor replaceDominatedUsesWith to have a flag to control whether to replace uses in BB itself.

Summary: This is in preparation for LoopSink pass which calls replaceDominatedUsesWith to update after sinking.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280949 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-08 15:25:12 +00:00
Dehao Chen d21744e2b8 Refactor replaceDominatedUsesWith to have a flag to control whether to replace uses in BB itself.
Summary: This is in preparation for LoopSink pass which calls replaceDominatedUsesWith to update after sinking.

Reviewers: chandlerc, davidxl, danielcdh

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D24170

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280427 91177308-0d34-0410-b5e6-96231b3b80d8
2016-09-01 23:26:48 +00:00
Eli Friedman 97b394f6af [JumpThreading] Fix handling of aliasing metadata.
Summary:
The correctness fix here is that when we CSE a load with another load,
we need to combine the metadata on the two loads. This matches the
behavior of other passes, like instcombine and GVN.

There's also a minor optimization improvement here: for load PRE, the
aliasing metadata on the inserted load should be the same as the
metadata on the original load. Not sure why the old code was throwing
it away.

Issue found by inspection.

Differential Revision: http://reviews.llvm.org/D21460

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277977 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-08 04:10:22 +00:00
Benjamin Kramer 284030ab2c Move helpers into anonymous namespaces. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277916 91177308-0d34-0410-b5e6-96231b3b80d8
2016-08-06 11:13:10 +00:00
Evgeniy Stepanov b57cbbd54d [sanitizer] Simplify and future-proof maybeMarkSanitizerLibraryCallNoBuiltin().
Sanitizers set nobuiltin attribute on certain library functions to
avoid a situation where such function is neither instrumented nor
intercepted.

At the moment the list of interesting functions is hardcoded. This
change replaces it with logic based on
TargetLibraryInfo::hasOptimizedCodegen and the presense of readnone
function attribute (sanitizers are generally interested in memory
behavior of library functions).

This is expected to be a no-op change: the new logic matches exactly
the same set of functions.

r276771 (currently reverted) added mempcpy() to the list, breaking
MSan tests. With this change, r276771 can be safely re-landed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277086 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-28 23:45:15 +00:00
David Majnemer 2d83d8a394 [Utils] Simplify combineMetadata
Use a range-based for loop, no functional change is intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276600 91177308-0d34-0410-b5e6-96231b3b80d8
2016-07-25 02:21:19 +00:00
David Majnemer 23ee217fe1 Just a small cleanup
No functional change is intended

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273780 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-25 08:34:38 +00:00
David Majnemer db5173a31d Revert "[SimplifyCFG] Stop inserting calls to llvm.trap for UB"
This reverts commit r273778, it seems to break UBSan :/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273779 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-25 08:19:55 +00:00
David Majnemer 46e1183e69 [SimplifyCFG] Stop inserting calls to llvm.trap for UB
SimplifyCFG had logic to insert calls to llvm.trap for two very
particular IR patterns: stores and invokes of undef/null.

While InstCombine canonicalizes certain undefined behavior IR patterns
to stores of undef, phase ordering means that this cannot be relied upon
in general.

There are much better tools than llvm.trap: UBSan and ASan.

N.B. I could be argued into reverting this change if a clear argument as
to why it is important that we synthesize llvm.trap for stores, I'd be
hard pressed to see why it'd be useful for invokes...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273778 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-25 08:04:19 +00:00
David Majnemer ae15013971 [SimplifyCFG] Replace calls to null/undef with unreachable
Calling null is undefined behavior, a call to undef can be trivially
treated as a call to null.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273776 91177308-0d34-0410-b5e6-96231b3b80d8
2016-06-25 07:37:27 +00:00