215 Commits

Author SHA1 Message Date
Stefan Stipanovic
52d4c048b3 [Attributor] Deduce "nosync" function attribute.
Introduce and deduce "nosync" function attribute to indicate that a function
does not synchronize with another thread in a way that other thread might free memory.

Reviewers: jdoerfert, jfb, nhaehnle, arsenm

Subscribers: wdng, hfinkel, nhaenhle, mehdi_amini, steven_wu,
dexonsmith, arsenm, uenoku, hiraditya, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D62766

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365830 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-11 21:37:40 +00:00
Vedant Kumar
0edfaf6dd2 [CodeExtractor] Fix sinking of allocas with multiple bitcast uses (PR42451)
An alloca which can be sunk into the extraction region may have more
than one bitcast use. Move these uses along with the alloca to prevent
use-before-def.

Testing: check-llvm, stage2 build of clang

Fixes llvm.org/PR42451.

Differential Revision: https://reviews.llvm.org/D64463

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365660 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-10 16:32:20 +00:00
Vedant Kumar
899d0e6438 [CodeExtractor] Simplify findAllocas, NFC
Split getLifetimeMarkers out into its own method and have it return a
struct.

Differential Revision: https://reviews.llvm.org/D64467

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365659 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-10 16:32:16 +00:00
Brian Homerding
7597e7f179 Add, and infer, a nofree function attribute
This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., free,
C++'s operator delete).

Reviewers: jdoerfert

Differential Revision: https://reviews.llvm.org/D49165


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365336 91177308-0d34-0410-b5e6-96231b3b80d8
2019-07-08 15:57:56 +00:00
Johannes Doerfert
8a0fc5ba4f [Attr] Add "willreturn" function attribute
This patch introduces a new function attribute, willreturn, to indicate
that a call of this function will either exhibit undefined behavior or
comes back and continues execution at a point in the existing call stack
that includes the current invocation.

This attribute guarantees that the function does not have any endless
loops, endless recursion, or terminating functions like abort or exit.

Patch by Hideto Ueno (@uenoku)

Reviewers: jdoerfert

Subscribers: mehdi_amini, hiraditya, steven_wu, dexonsmith, lebedev.ri, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62801

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364555 91177308-0d34-0410-b5e6-96231b3b80d8
2019-06-27 15:51:40 +00:00
Quentin Colombet
5742615005 [CodeExtractor] Add a few debug lines to understand why a region is not extracted
The CodeExtractor is not smart enough to compute which basic block is
the entry of a region. Instead it relies on the order of the list
of basic blocks that is handed to it and assumes that the entry
is the first block in the list.

Without the additional debug information, it is hard to understand
why a valid region does not get extracted, because we would miss
that the order of in the list just doesn't match what the CodeExtractor
wants.

NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358471 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-16 02:12:05 +00:00
Fangrui Song
360e56327d Change some dyn_cast to more apropriate isa. NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357773 91177308-0d34-0410-b5e6-96231b3b80d8
2019-04-05 16:16:23 +00:00
Matt Arsenault
6e8fb99b69 IR: Add immarg attribute
This indicates an intrinsic parameter is required to be a constant,
and should not be replaced with a non-constant value.

Add the attribute to all AMDGPU and generic intrinsics that comments
indicate it should apply to. I scanned other target intrinsics, but I
don't see any obvious comments indicating which arguments are intended
to be only immediates.

This breaks one questionable testcase for the autoupgrade. I'm unclear
on whether the autoupgrade is supposed to really handle declarations
which were never valid. The verifier fails because the attributes now
refer to a parameter past the end of the argument list.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355981 91177308-0d34-0410-b5e6-96231b3b80d8
2019-03-12 21:02:54 +00:00
Vedant Kumar
c26f76b367 [CodeExtractor] Do not lift lifetime.end markers for region inputs
If a lifetime.end marker occurs along one path through the extraction
region, but not another, then it's still incorrect to lift the marker,
because there is some path through the extracted function which would
ordinarily not reach the marker. If the call to the extracted function
is in a loop, unrolling can cause inputs to the function to become
optimized out as undef after the first iteration.

To prevent incorrect stack slot merging in the calling function, it
should be sufficient to lift lifetime.start markers for region inputs.
I've tested this theory out by doing a stage2 check-all with randomized
splitting enabled.

This is a follow-up to r353973, and there's additional context for this
change in https://reviews.llvm.org/D57834.

rdar://47896986

Differential Revision: https://reviews.llvm.org/D58253

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354159 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-15 18:46:58 +00:00
Vedant Kumar
18afa443d9 [CodeExtractor] Only lift lifetime markers present in the extraction region
When CodeExtractor finds liftime markers referencing inputs to the
extraction region, it lifts these markers out of the region and inserts
them around the call to the extracted function (see r350420, PR39671).

However, it should *only* lift lifetime markers that are actually
present in the extraction region. I.e., if a start marker is present in
the extraction region but a corresponding end marker isn't (or vice
versa), only the start marker (or end marker, resp.) should be lifted.

Differential Revision: https://reviews.llvm.org/D57834

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353973 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-13 19:53:38 +00:00
Vedant Kumar
9025db3ce7 [CodeExtractor] Restore outputs after creating exit stubs
When CodeExtractor saves the result of InvokeInst at the first insertion
point of the 'normal destination' basic block, this block can be omitted
in the outlined region, so store is placed outside of the function. The
suggested solution is to process saving outputs after creating exit
stubs for new function, and stores will be placed in that blocks before
return in this case.

Patch by Sergei Kachkov!

Fixes llvm.org/PR40455.

Differential Revision: https://reviews.llvm.org/D57919

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353562 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-08 20:48:04 +00:00
Sergey Dmitriev
9a22bfd50b [CodeExtractor] Update function's assumption cache after extracting blocks from it
Summary: Assumption cache's self-updating mechanism does not correctly handle the case when blocks are extracted from the function by the CodeExtractor. As a result function's assumption cache may have stale references to the llvm.assume calls that were moved to the outlined function. This patch fixes this problem by removing extracted llvm.assume calls from the function’s assumption cache.

Reviewers: hfinkel, vsk, fhahn, davidxl, sanjoy

Reviewed By: hfinkel, vsk

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57215

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353500 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-08 06:55:18 +00:00
James Y Knight
6c00b3f35f [opaque pointer types] Pass value type to LoadInst creation.
This cleans up all LoadInst creation in LLVM to explicitly pass the
value type rather than deriving it from the pointer's element-type.

Differential Revision: https://reviews.llvm.org/D57172

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352911 91177308-0d34-0410-b5e6-96231b3b80d8
2019-02-01 20:44:24 +00:00
Vedant Kumar
acc14ca88d [CodeExtractor] Add support for the swifterror attribute
When passing a `swifterror` argument or alloca as an input to an
extraction region, mark the input parameter `swifterror`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352408 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-28 19:13:37 +00:00
Julian Lettner
a1e328df4a Revert "[Sanitizers] UBSan unreachable incompatible with ASan in the presence of noreturn calls"
This reverts commit cea84ab93aeb079a358ab1c8aeba6d9140ef8b47.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352069 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-24 18:04:21 +00:00
Julian Lettner
2e1beed270 [Sanitizers] UBSan unreachable incompatible with ASan in the presence of noreturn calls
Summary:
UBSan wants to detect when unreachable code is actually reached, so it
adds instrumentation before every `unreachable` instruction. However,
the optimizer will remove code after calls to functions marked with
`noreturn`. To avoid this UBSan removes `noreturn` from both the call
instruction as well as from the function itself. Unfortunately, ASan
relies on this annotation to unpoison the stack by inserting calls to
`_asan_handle_no_return` before `noreturn` functions. This is important
for functions that do not return but access the the stack memory, e.g.,
unwinder functions *like* `longjmp` (`longjmp` itself is actually
"double-proofed" via its interceptor). The result is that when ASan and
UBSan are combined, the `noreturn` attributes are missing and ASan
cannot unpoison the stack, so it has false positives when stack
unwinding is used.

Changes:
  # UBSan now adds the `expect_noreturn` attribute whenever it removes
    the `noreturn` attribute from a function
  # ASan additionally checks for the presence of this attribute

Generated code:
```
call void @__asan_handle_no_return    // Additionally inserted to avoid false positives
call void @longjmp
call void @__asan_handle_no_return
call void @__ubsan_handle_builtin_unreachable
unreachable
```

The second call to `__asan_handle_no_return` is redundant. This will be
cleaned up in a follow-up patch.

rdar://problem/40723397

Reviewers: delcypher, eugenis

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D56624

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@352003 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-24 01:06:19 +00:00
Chandler Carruth
6b547686c5 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351636 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 08:50:56 +00:00
Vedant Kumar
8175d01f18 [CodeExtractor] Emit lifetime markers around reloads of outputs
CodeExtractor permits extracting a region of blocks from a function even
when values defined within the region are used outside of it.

This is typically done by creating an alloca in the original function
and reloading the alloca after a call to the extracted function.

Wrap the reload in lifetime start/end markers to promote stack coloring.

Suggested by Sergei Kachkov!

Differential Revision: https://reviews.llvm.org/D56045

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351621 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-19 02:37:59 +00:00
Vedant Kumar
bbbee1ff50 [CodeExtractor] Do not extract unsafe lifetime markers
Lifetime markers which reference inputs to the extraction region are not
safe to extract. Example ('rhs' will be extracted):

```
               entry:
              +------------+
              | x = alloca |
              | y = alloca |
              +------------+
             /              \
   lhs:                      rhs:
  +-------------------+     +-------------------+
  | lifetime_start(x) |     | lifetime_start(x) |
  | use(x)            |     | lifetime_start(y) |
  | lifetime_end(x)   |     | use(x, y)         |
  | lifetime_start(y) |     | lifetime_end(y)   |
  | use(y)            |     | lifetime_end(x)   |
  | lifetime_end(y)   |     +-------------------+
  +-------------------+
```

Prior to extraction, the stack coloring pass sees that the slots for 'x'
and 'y' are in-use at the same time. After extraction, the coloring pass
infers that 'x' and 'y' are *not* in-use concurrently, because markers
from 'rhs' are no longer available to help decide otherwise.

This leads to a miscompile, because the stack slots actually are in-use
concurrently in the extracted function.

Fix this by moving lifetime start/end markers for memory regions defined
in the calling function around the call to the extracted function.

Fixes llvm.org/PR39671 (rdar://45939472).

Differential Revision: https://reviews.llvm.org/D55967

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350420 91177308-0d34-0410-b5e6-96231b3b80d8
2019-01-04 17:43:22 +00:00
Vedant Kumar
eeb1971b1c [IR] Add Instruction::isLifetimeStartOrEnd, NFC
Instruction::isLifetimeStartOrEnd() checks whether an Instruction is an
llvm.lifetime.start or an llvm.lifetime.end intrinsic.

This was suggested as a cleanup in D55967.

Differential Revision: https://reviews.llvm.org/D56019

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349964 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-21 21:49:40 +00:00
Vedant Kumar
35741b0bf7 [CodeExtractor] Store outputs at the first valid insertion point
When CodeExtractor outlines values which are used by the original
function, it must store those values in some in-out parameter. This
store instruction must not be inserted in between a PHI and an EH pad
instruction, as that results in invalid IR.

This fixes the following verifier failure seen while outlining within
ObjC methods with live exit values:

  The unwind destination does not have an exception handling instruction!
    %call35 = invoke i8* bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to i8* (i8*, i8*)*)(i8* %exn.adjusted, i8* %1)
            to label %invoke.cont34 unwind label %lpad33, !dbg !4183
  The unwind destination does not have an exception handling instruction!
    invoke void @objc_exception_throw(i8* %call35) #12
            to label %invoke.cont36 unwind label %lpad33, !dbg !4184
  LandingPadInst not the first non-PHI instruction in the block.
    %3 = landingpad { i8*, i32 }
            catch i8* null, !dbg !1411

rdar://46540815

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@348562 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-07 03:01:54 +00:00
Vedant Kumar
e1363b44fe [CodeExtractor] Do not marked outlined calls which may resume EH as noreturn
Treat terminators which resume exception propagation as returning instructions
(at least, for the purposes of marking outlined functions `noreturn`). This is
to avoid inserting traps after calls to outlined functions which unwind.

rdar://46129950

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@348404 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-05 19:35:37 +00:00
Vedant Kumar
f00f55a81f [CodeExtractor] Split PHI nodes with incoming values from outlined region (PR39433)
If a PHI node out of extracted region has multiple incoming values from it,
split this PHI on two parts. First PHI has incomings only from region and
extracts with it (they are placed to the separate basic block that added to the
list of outlined), and incoming values in original PHI are replaced by first
PHI. Similar solution is already used in CodeExtractor for PHIs in entry block
(severSplitPHINodes method). It covers PR39433 bug.

Patch by Sergei Kachkov!

Differential Revision: https://reviews.llvm.org/D55018

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@348205 91177308-0d34-0410-b5e6-96231b3b80d8
2018-12-03 22:40:21 +00:00
Vedant Kumar
da31f7b670 [CodeExtractor] Mark functions noreturn when applicable
This eliminates the outlining penalty for llvm.trap/unreachable, because
callers no longer have to emit cleanup/ret instructions after calling an
outlined `noreturn` function.

rdar://45523626

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346421 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-08 17:57:09 +00:00
Vedant Kumar
2b75576214 [CodeExtractor] Do not extract calls to eh_typeid_for (PR39545)
The lowering for a call to eh_typeid_for changes when it's moved from
one function to another.

There are several proposals for fixing this issue in llvm.org/PR39545.
Until some solution is in place, do not allow CodeExtractor to extract
calls to eh_typeid_for, as that results in serious miscompilations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346256 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 19:06:08 +00:00
Vedant Kumar
b109c4206a [CodeExtractor] Erase use-without-def debug intrinsics in parent func
When CodeExtractor moves instructions to a new function, debug
intrinsics referring to those instructions within the parent function
become invalid.

This results in the same verifier failure which motivated r344545, about
function-local metadata being used in the wrong function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@346255 91177308-0d34-0410-b5e6-96231b3b80d8
2018-11-06 19:05:53 +00:00
Vedant Kumar
c0bb0349d7 [HotColdSplitting] Identify larger cold regions using domtree queries
The current splitting algorithm works in three stages:

  1) Identify cold blocks, then
  2) Use forward/backward propagation to mark hot blocks, then
  3) Grow a SESE region of blocks *outside* of the set of hot blocks and
  start outlining.

While testing this pass on Apple internal frameworks I noticed that some
kinds of control flow (e.g. loops) are never outlined, even though they
unconditionally lead to / follow cold blocks. I noticed two other issues
related to how cold regions are identified:

  - An inconsistency can arise in the internal state of the hotness
  propagation stage, as a block may end up in both the ColdBlocks set
  and the HotBlocks set. Further inconsistencies can arise as these sets
  do not match what's in ProfileSummaryInfo.

  - It isn't necessary to limit outlining to single-exit regions.

This patch teaches the splitting algorithm to identify maximal cold
regions and outline them. A maximal cold region is defined as the set of
blocks post-dominated by a cold sink block, or dominated by that sink
block. This approach can successfully outline loops in the cold path. As
a side benefit, it maintains less internal state than the current
approach.

Due to a limitation in CodeExtractor, blocks within the maximal cold
region which aren't dominated by a single entry point (a so-called "max
ancestor") are filtered out.

Results:
  - X86 (LNT + -Os + externals): 134KB of TEXT were outlined compared to
  47KB pre-patch, or a ~3x improvement. Did not see a performance impact
  across two runs.
  - AArch64 (LNT + -Os + externals + Apple-internal benchmarks): 149KB
  of TEXT were outlined. Ditto re: performance impact.
  - Outlining results improve marginally in the internal frameworks I
  tested.

Follow-ups:
  - Outline more than once per function, outline large single basic
  blocks, & try to remove unconditional branches in outlined functions.

Differential Revision: https://reviews.llvm.org/D53627

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345209 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-24 22:15:41 +00:00
Teresa Johnson
0c69da83b3 [hot-cold-split] Name split functions with ".cold" suffix
Summary:
The current default of appending "_"+entry block label to the new
extracted cold function breaks demangling. Change the deliminator from
"_" to "." to enable demangling. Because the header block label will
be empty for release compile code, use "extracted" after the "." when
the label is empty.

Additionally, add a mechanism for the client to pass in an alternate
suffix applied after the ".", and have the hot cold split pass use
"cold."+Count, where the Count is currently 1 but can be used to
uniquely number multiple cold functions split out from the same function
with D53588.

Reviewers: sebpop, hiraditya

Subscribers: llvm-commits, erik.pilkington

Differential Revision: https://reviews.llvm.org/D53534

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@345178 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-24 18:53:47 +00:00
Chandler Carruth
7d0753a001 [TI removal] Update CodeExtractor to use Instruction directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344716 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-18 00:38:54 +00:00
Vedant Kumar
0a2a30e517 [CodeExtractor] Erase debug intrinsics in outlined thunks (fix PR22900)
Variable updates within the outlined function are invisible to
debuggers. This could be improved by defining a DISubprogram for the
new function. For the moment, simply erase the debug intrinsics instead.

This fixes verifier failures about function-local metadata being used in
the wrong function, seen while testing the hot/cold splitting pass.

rdar://45142482

Differential Revision: https://reviews.llvm.org/D53267

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344545 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-15 19:22:20 +00:00
Chandler Carruth
2aaf7228e0 [TI removal] Make variables declared as TerminatorInst and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344502 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-15 10:04:59 +00:00
Chandler Carruth
d2b1fb11d3 [x86/SLH] Add a real Clang flag and LLVM IR attribute for Speculative
Load Hardening.

Wires up the existing pass to work with a proper IR attribute rather
than just a hidden/internal flag. The internal flag continues to work
for now, but I'll likely remove it soon.

Most of the churn here is adding the IR attribute. I talked about this
Kristof Beyls and he seemed at least initially OK with this direction.
The idea of using a full attribute here is that we *do* expect at least
some forms of this for other architectures. There isn't anything
*inherently* x86-specific about this technique, just that we only have
an implementation for x86 at the moment.

While we could potentially expose this as a Clang-level attribute as
well, that seems like a good question to defer for the moment as it
isn't 100% clear whether that or some other programmer interface (or
both?) would be best. We'll defer the programmer interface side of this
for now, but at least get to the point where the feature can be enabled
without relying on implementation details.

This also allows us to do something that was really hard before: we can
enable *just* the indirect call retpolines when using SLH. For x86, we
don't have any other way to mitigate indirect calls. Other architectures
may take a different approach of course, and none of this is surfaced to
user-level flags.

Differential Revision: https://reviews.llvm.org/D51157

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@341363 91177308-0d34-0410-b5e6-96231b3b80d8
2018-09-04 12:38:00 +00:00
Alexander Richardson
47ff67b78d Allow creating llvm::Function in non-zero address spaces
Most users won't have to worry about this as all of the
'getOrInsertFunction' functions on Module will default to the program
address space.

An overload has been added to Function::Create to abstract away the
details for most callers.

This is based on https://reviews.llvm.org/D37054 but without the changes to
make passing a Module to Function::Create() mandatory. I have also added
some more tests and fixed the LLParser to accept call instructions for
types in the program address space.

Reviewed By: bjope

Differential Revision: https://reviews.llvm.org/D47541

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340519 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-23 09:25:17 +00:00
Florian Hahn
bfa8bdbeb4 [CodeExtractor] Use 'normal destination' BB as insert point to store invoke results.
Currently CodeExtractor tries to use the next node after an invoke to
place the store for the result of the invoke, if it is an out parameter
of the region. This fails, as the invoke terminates the current BB.
In that case, we can place the store in the 'normal destination' BB, as
the result will only be available in that case.


Reviewers: davidxl, davide, efriedma

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D51037


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@340331 91177308-0d34-0410-b5e6-96231b3b80d8
2018-08-21 20:07:46 +00:00
Fangrui Song
af7b1832a0 Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@338293 91177308-0d34-0410-b5e6-96231b3b80d8
2018-07-30 19:41:25 +00:00
Nicola Zaghen
0818e789cb Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332240 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-14 12:53:11 +00:00
Sergey Dmitriev
a09145e6dd [CodeExtractor] Allow extracting blocks with exception handling
This is a CodeExtractor improvement which adds support for extracting blocks
which have exception handling constructs if that is legal to do. CodeExtractor
performs validation checks to ensure that extraction is legal when it finds
invoke instructions or EH pads (landingpad, catchswitch, or cleanuppad) in
blocks to be extracted.

I have also added an option to allow extraction of blocks with alloca
instructions, but no validation is done for allocas. CodeExtractor caller has
to validate it himself before allowing alloca instructions to be extracted.
By default allocas are still not allowed in extraction blocks.

Differential Revision: https://reviews.llvm.org/D45904


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332151 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-11 22:49:49 +00:00
Adrian Prantl
26b584c691 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331272 91177308-0d34-0410-b5e6-96231b3b80d8
2018-05-01 15:54:18 +00:00
Vlad Tsyrklevich
45013b2e67 Add the ShadowCallStack attribute
Summary:
Introduce the ShadowCallStack function attribute. It's added to
functions compiled with -fsanitize=shadow-call-stack in order to mark
functions to be instrumented by a ShadowCallStack pass to be submitted
in a separate change.

Reviewers: pcc, kcc, kubamracek

Reviewed By: pcc, kcc

Subscribers: cryptoad, mehdi_amini, javed.absar, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44800

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@329108 91177308-0d34-0410-b5e6-96231b3b80d8
2018-04-03 20:10:40 +00:00
Matt Morehouse
7d085b607d [SimplifyCFG] Create attribute for fuzzing-specific optimizations.
Summary:
When building with libFuzzer, converting control flow to selects or
obscuring the original operands of CMPs reduces the effectiveness of
libFuzzer's heuristics.

This patch provides an attribute to disable or modify certain optimizations
for optimal fuzzing signal.

Provides a less aggressive alternative to https://reviews.llvm.org/D44057.

Reviewers: vitalybuka, davide, arsenm, hfinkel

Reviewed By: vitalybuka

Subscribers: junbuml, mehdi_amini, wdng, javed.absar, hiraditya, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44232

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328214 91177308-0d34-0410-b5e6-96231b3b80d8
2018-03-22 17:07:51 +00:00
Oren Ben Simhon
10c992c085 [X86] Added support for nocf_check attribute for indirect Branch Tracking
X86 Supports Indirect Branch Tracking (IBT) as part of Control-Flow Enforcement Technology (CET).
IBT instruments ENDBR instructions used to specify valid targets of indirect call / jmp.
The `nocf_check` attribute has two roles in the context of X86 IBT technology:
	1. Appertains to a function - do not add ENDBR instruction at the beginning of the function.
	2. Appertains to a function pointer - do not track the target function of this pointer by adding nocf_check prefix to the indirect-call instruction.

This patch implements `nocf_check` context for Indirect Branch Tracking.
It also auto generates `nocf_check` prefixes before indirect branchs to jump tables that are guarded by range checks.

Differential Revision: https://reviews.llvm.org/D41879

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@327767 91177308-0d34-0410-b5e6-96231b3b80d8
2018-03-17 13:29:46 +00:00
Easwaran Raman
fd335155cc Add a ProfileCount class to represent entry counts.
Summary:
The class wraps a uint64_t and an enum to represent the type of profile
count (real and synthetic) with some helper methods.

Reviewers: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41883

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322771 91177308-0d34-0410-b5e6-96231b3b80d8
2018-01-17 22:24:23 +00:00
Florian Hahn
8eaf38e0eb [CodeExtractor] Use subset of function attributes for extracted function.
In addition to target-dependent attributes, we can also preserve a
white-listed subset of target independent function attributes. The white-list
excludes problematic attributes, most prominently:

* attributes related to memory accesses, as alloca instructions
  could be moved in/out of the extracted block

* control-flow dependent attributes, like no_return or thunk, as the
  relerelevant instructions might or might not get extracted.

Thanks @efriedma and @aemerson for providing a set of attributes that cannot be
propagated.


Reviewers: efriedma, davidxl, davide, silvas

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D41334


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321961 91177308-0d34-0410-b5e6-96231b3b80d8
2018-01-07 11:22:25 +00:00
Florian Hahn
976af3f5de [CodeExtractor] Add debug locations for new call and branch instrs.
Summary:
If a partially inlined function has debug info, we have to add debug
locations to the call instruction calling the outlined function.
We use the debug location of the first instruction in the outlined
function, as the introduced call transfers control to this statement and
there is no other equivalent line in the source code.

We also use the same debug location for the branch instruction added
to jump from artificial entry block for the outlined function, which just
jumps to the first actual basic block of the outlined function.

Reviewers: davide, aprantl, rriddle, dblaikie, danielcdh, wmi

Reviewed By: aprantl, rriddle, danielcdh

Subscribers: eraman, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D40413

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320199 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-08 21:49:03 +00:00
Florian Hahn
0b4ce86d63 [CodeExtractor] Add missing AllowVarArgs initialization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318029 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-13 11:08:47 +00:00
Florian Hahn
0e6bdca6cc [PartialInliner] Inline vararg functions that forward varargs.
Summary:
This patch extends the partial inliner to support inlining parts of
vararg functions, if the vararg handling is done in the outlined part.

It adds a `ForwardVarArgsTo` argument to InlineFunction. If it is
non-null, all varargs passed to the inlined function will be added to
all calls to `ForwardVarArgsTo`.

The partial inliner takes care to only pass `ForwardVarArgsTo` if the
varargs handing is done in the outlined function. It checks that vastart
is not part of the function to be inlined.

`test/Transforms/CodeExtractor/PartialInlineNoInline.ll` (already part
of the repo) checks we do not do partial inlining if vastart is used in
a basic block that will be inlined.

Reviewers: davide, davidxl, grosser

Reviewed By: davide, davidxl, grosser

Subscribers: gyiu, grosser, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D39607

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318028 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-13 10:35:52 +00:00
Florian Hahn
81b03a3889 [CodeExtractor] Fix iterator invalidation in findOrCreateBlockForHoisting.
Summary:
By replacing branches to CommonExitBlock, we remove the node from
CommonExitBlock's predecessors, invalidating the iterator. The problem
is exposed when the common exit block has multiple predecessors and
needs to sink lifetime info. The modification in the test case trigger
the issue.

Reviewers: davidxl, davide, wmi

Reviewed By: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D39112

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317084 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01 09:48:12 +00:00
Eugene Zelenko
761e543ac7 [Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315516 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-11 21:41:43 +00:00
Jakub Kuderski
bcebc16153 [CodeExtractor] Fix multiple bugs under certain shape of extracted region
Summary:
If the extracted region has multiple exported data flows toward the same BB which is not included in the region, correct resotre instructions and PHI nodes won't be generated inside the exitStub. The solution is simply put the restore instructions right after the definition of output values instead of putting in exitStub.
Unittest for this bug is included.

Author: myhsu

Reviewers: chandlerc, davide, lattner, silvas, davidxl, wmi, kuhar

Subscribers: dberlin, kuhar, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D37902

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315041 91177308-0d34-0410-b5e6-96231b3b80d8
2017-10-06 03:37:06 +00:00
Davide Italiano
7617a49931 [CodeExtractor] Remove unneded and commented out debugging stmts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306966 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-02 00:07:18 +00:00