Commit Graph

1023 Commits

Author SHA1 Message Date
Vedant Kumar bbc953fed4 [ubsan] Null-check pointers in -fsanitize=vptr (PR33881)
The instrumentation generated by -fsanitize=vptr does not null check a
user pointer before loading from it. This causes crashes in the face of
UB member calls (this=nullptr), i.e it's causing user programs to crash
only after UBSan is turned on.

The fix is to make run-time null checking a prerequisite for enabling
-fsanitize=vptr, and to then teach UBSan to reuse these run-time null
checks to make -fsanitize=vptr safe.

Testing: check-clang, check-ubsan, a stage2 ubsan-enabled build

Differential Revision: https://reviews.llvm.org/D35735

https://bugs.llvm.org/show_bug.cgi?id=33881

llvm-svn: 309007
2017-07-25 19:34:23 +00:00
Yaxun Liu 9d33fb1bc5 CodeGen: Insert addr space cast for automatic/temp var at right position
The uses of alloca may be in different blocks other than the block containing the alloca.
Therefore if the alloca addr space is non-zero and it needs to be casted to default
address space, the cast needs to be inserted in the same BB as the alloca insted of
the current builder insert point since the current insert point may be in a different BB.

Differential Revision: https://reviews.llvm.org/D35438

llvm-svn: 308313
2017-07-18 14:46:03 +00:00
Vedant Kumar 175b6d1f28 [ubsan] Teach the pointer overflow check that "p - <unsigned> <= p" (PR33430)
The pointer overflow check gives false negatives when dealing with
expressions in which an unsigned value is subtracted from a pointer.
This is summarized in PR33430 [1]: ubsan permits the result of the
subtraction to be greater than "p", but it should not.

To fix the issue, we should track whether or not the pointer expression
is a subtraction. If it is, and the indices are unsigned, we know to
expect "p - <unsigned> <= p".

I've tested this by running check-{llvm,clang} with a stage2
ubsan-enabled build. I've also added some tests to compiler-rt, which
are in D34122.

[1] https://bugs.llvm.org/show_bug.cgi?id=33430

Differential Revision: https://reviews.llvm.org/D34121

llvm-svn: 307955
2017-07-13 20:55:26 +00:00
Yaxun Liu cbf647cc3a CodeGen: Fix address space of global variable
Certain targets (e.g. amdgcn) require global variable to stay in global or constant address
space. In C or C++ global variables are emitted in the default (generic) address space.
This patch introduces virtual functions TargetCodeGenInfo::getGlobalVarAddressSpace
and TargetInfo::getConstantAddressSpace to handle this in a general approach.

It only affects IR generated for amdgcn target.

Differential Revision: https://reviews.llvm.org/D33842

llvm-svn: 307470
2017-07-08 13:24:52 +00:00
Yaxun Liu 84744c152a CodeGen: Cast temporary variable to proper address space
In C++ all variables are in default address space. Previously change has been
made to cast automatic variables to default address space. However that is
not sufficient since all temporary variables need to be casted to default
address space.

This patch casts all temporary variables to default address space except those
for passing indirect arguments since they are only used for load/store.

This patch only affects target having non-zero alloca address space.

Differential Revision: https://reviews.llvm.org/D33706

llvm-svn: 305711
2017-06-19 17:03:41 +00:00
Vedant Kumar c420d14b29 [ubsan] PR33081: Skip the standard type checks for volatile
Skip checks for null dereference, alignment violation, object size
violation, and dynamic type violation if the pointer points to volatile
data.

Differential Revision: https://reviews.llvm.org/D34262

llvm-svn: 305546
2017-06-16 03:27:36 +00:00
Eric Fiselier cddaf8728f [coroutines] Allow co_await and co_yield expressions that return an lvalue to compile
Summary:
The title says it all.


Reviewers: GorNishanov, rsmith

Reviewed By: GorNishanov

Subscribers: rjmccall, cfe-commits

Differential Revision: https://reviews.llvm.org/D34194

llvm-svn: 305496
2017-06-15 19:43:36 +00:00
Vedant Kumar 6dbf4274a5 [ubsan] Detect invalid unsigned pointer index expression (clang)
Adding an unsigned offset to a base pointer has undefined behavior if
the result of the expression would precede the base. An example from
@regehr:

  int foo(char *p, unsigned offset) {
    return p + offset >= p; // This may be optimized to '1'.
  }

  foo(p, -1); // UB.

This patch extends the pointer overflow check in ubsan to detect invalid
unsigned pointer index expressions. It changes the instrumentation to
only permit non-negative offsets in pointer index expressions when all
of the GEP indices are unsigned.

Testing: check-llvm, check-clang run on a stage2, ubsan-instrumented
build.

Differential Revision: https://reviews.llvm.org/D33910

llvm-svn: 305216
2017-06-12 18:42:51 +00:00
Alexey Bataev 56223237b0 [DebugInfo] Add kind of ImplicitParamDecl for emission of FlagObjectPointer.
Summary:
If the first parameter of the function is the ImplicitParamDecl, codegen
automatically marks it as an implicit argument with `this` or `self`
pointer. Added internal kind of the ImplicitParamDecl to separate
'this', 'self', 'vtt' and other implicit parameters from other kind of
parameters.

Reviewers: rjmccall, aaron.ballman

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D33735

llvm-svn: 305075
2017-06-09 13:40:18 +00:00
Simon Pilgrim a5dbbc6ead Don't assume that a store source is a vector type just because the destination is (PR26099)
llvm-svn: 304465
2017-06-01 20:13:34 +00:00
Vedant Kumar a125eb55cb [ubsan] Add a check for pointer overflow UB
Check pointer arithmetic for overflow.

For some more background on this check, see:

  https://wdtz.org/catching-pointer-overflow-bugs.html
  https://reviews.llvm.org/D20322

Patch by Will Dietz and John Regehr!

This version of the patch is different from the original in a few ways:

  - It introduces the EmitCheckedInBoundsGEP utility which inserts
    checks when the pointer overflow check is enabled.

  - It does some constant-folding to reduce instrumentation overhead.

  - It does not check some GEPs in CGExprCXX. I'm not sure that
    inserting checks here, or in CGClass, would catch many bugs.

Possible future directions for this check:

  - Introduce CGF.EmitCheckedStructGEP, to detect overflows when
    accessing structures.

Testing: Apart from the added lit test, I ran check-llvm and check-clang
with a stage2, ubsan-instrumented clang. Will and John have also done
extensive testing on numerous open source projects.

Differential Revision: https://reviews.llvm.org/D33305

llvm-svn: 304459
2017-06-01 19:22:18 +00:00
Piotr Padlewski c1d26062f7 Emit invariant.group.barrier when using union field
Summary:
We need to emit barrier if the union field
is CXXRecordDecl because it might have vptrs. The testcode
was wrongly devirtualized. It also proves that having different
groups for different dynamic types is not sufficient.

Reviewers: rjmccall, rsmith, mehdi_amini

Subscribers: amharc, cfe-commits

Differential Revision: https://reviews.llvm.org/D31830

llvm-svn: 304448
2017-06-01 18:39:34 +00:00
Krzysztof Parzyszek 5960a57ef7 [CodeGen] Pessimize aliasing for member unions (and may-alias) objects
Use the TBAA info of the omnipotent char for these objects.

Differential Revision: https://reviews.llvm.org/D33328

llvm-svn: 303851
2017-05-25 12:55:47 +00:00
Krzysztof Parzyszek 8f248234fa [CodeGen] Propagate LValueBaseInfo instead of AlignmentSource
The functions creating LValues propagated information about alignment
source. Extend the propagated data to also include information about
possible unrestricted aliasing. A new class LValueBaseInfo will
contain both AlignmentSource and MayAlias info.

This patch should not introduce any functional changes.

Differential Revision: https://reviews.llvm.org/D33284

llvm-svn: 303358
2017-05-18 17:07:11 +00:00
Serge Guelton 1d993270b3 Suppress all uses of LLVM_END_WITH_NULL. NFC.
Use variadic templates instead of relying on <cstdarg> + sentinel.

This enforces better type checking and makes code more readable.

Differential revision: https://reviews.llvm.org/D32550

llvm-svn: 302572
2017-05-09 19:31:30 +00:00
Vedant Kumar 6b22dda5a3 [ubsan] nullability-assign: Check assignments into C++ structs
Fix the nullability-assign check so that it can handle assignments into
C++ structs. Previously, such assignments were not instrumented.

Testing: check-clang, check-ubsan, enabling the existing test in ObjC++
mode, and building some Apple frameworks with -fsanitize=nullability.

llvm-svn: 301482
2017-04-26 21:55:17 +00:00
Vedant Kumar e859ebbd06 [ubsan] Skip alignment checks on allocas with known alignment
It's possible to determine the alignment of an alloca at compile-time.
Use this information to skip emitting some runtime alignment checks.

Testing: check-clang, check-ubsan.

This significantly reduces the amount of alignment checks we emit when
compiling X86ISelLowering.cpp. Here are the numbers from patched/unpatched
clangs based on r301361.

  ------------------------------------------
  | Setup          | # of alignment checks |
  ------------------------------------------
  | unpatched, -O0 |                 47195 |
  | patched, -O0   |                 30876 | (-34.6%)
  ------------------------------------------

llvm-svn: 301377
2017-04-26 02:17:21 +00:00
Vedant Kumar dbbdda4d23 [ubsan] Skip null checks if they are constant-folded away
The IR builder can constant-fold null checks if the pointer operand
points to a constant. If the "is-non-null" check is folded away to
"true", don't emit the null check + branch.

Testing: check-clang, check-ubsan.

This slightly reduces the amount of null checks we emit when compiling
X86ISelLowering.cpp. Here are the numbers from patched/unpatched clangs
based on r300371.

  -------------------------------------
  | Setup          | # of null checks |
  -------------------------------------
  | unpatched, -O0 |            25251 |
  | patched, -O0   |            23925 | (-5.3%)
  -------------------------------------

llvm-svn: 300509
2017-04-17 22:26:10 +00:00
Vedant Kumar 379d9c1dc6 [ubsan] Skip null checks on pointers to the start of an alloca
Pointers to the start of an alloca are non-null, so we don't need to
emit runtime null checks for them.

Testing: check-clang, check-ubsan.

This significantly reduces the amount of null checks we emit when
compiling X86ISelLowering.cpp. Here are the numbers from patched /
unpatched clangs based on r300371.

  -------------------------------------
  | Setup          | # of null checks |
  -------------------------------------
  | unpatched, -O0 |            45439 |
  | patched, -O0   |            25251 | (-44.4%)
  -------------------------------------

llvm-svn: 300508
2017-04-17 22:26:07 +00:00
Vedant Kumar 116aebcae0 [ubsan] Don't check alignment if the alignment is 1
If a pointer is 1-byte aligned, there's no use in checking its
alignment. Somewhat surprisingly, ubsan can spend a significant amount
of time doing just that!

This loosely depends on D30283.

Testing: check-clang, check-ubsan, and a stage2 ubsan build.

Differential Revision: https://reviews.llvm.org/D30285

llvm-svn: 300371
2017-04-14 22:03:37 +00:00
Vedant Kumar ffd7c887d6 [ubsan] Reduce alignment checking of C++ object pointers
This patch teaches ubsan to insert an alignment check for the 'this'
pointer at the start of each method/lambda. This allows clang to emit
significantly fewer alignment checks overall, because if 'this' is
aligned, so are its fields.

This is essentially the same thing r295515 does, but for the alignment
check instead of the null check. One difference is that we keep the
alignment checks on member expressions where the base is a DeclRefExpr.
There's an opportunity to diagnose unaligned accesses in this situation
(as pointed out by Eli, see PR32630).

Testing: check-clang, check-ubsan, and a stage2 ubsan build.

Along with the patch from D30285, this roughly halves the amount of
alignment checks we emit when compiling X86FastISel.cpp. Here are the
numbers from patched/unpatched clangs based on r298160.

  ------------------------------------------
  | Setup          | # of alignment checks |
  ------------------------------------------
  | unpatched, -O0 |                 24326 |
  | patched, -O0   |                 12717 | (-47.7%)
  ------------------------------------------

Differential Revision: https://reviews.llvm.org/D30283

llvm-svn: 300370
2017-04-14 22:03:34 +00:00
Matt Arsenault 502ad60c8f Update for AllocaInst construction changes
llvm-svn: 299889
2017-04-10 22:28:02 +00:00
Evgeniy Stepanov 1a8030e737 [cfi] Emit __cfi_check stub in the frontend.
Previously __cfi_check was created in LTO optimization pipeline, which
means LLD has no way of knowing about the existence of this symbol
without rescanning the LTO output object. As a result, LLD fails to
export __cfi_check, even when given --export-dynamic-symbol flag.

llvm-svn: 299806
2017-04-07 23:00:38 +00:00
Jin-Gu Kang e7cdcdea73 Preserve vec3 type.
Summary: Preserve vec3 type with CodeGen option.

Reviewers: Anastasia, bruno

Reviewed By: Anastasia

Subscribers: bruno, ahatanak, cfe-commits

Differential Revision: https://reviews.llvm.org/D30810

llvm-svn: 299445
2017-04-04 16:40:25 +00:00
George Burgess IV a63f91574f Let llvm.objectsize be conservative with null pointers
D28494 adds another parameter to @llvm.objectsize. Clang needs to be
sure to pass that third arg whenever applicable.

llvm-svn: 298431
2017-03-21 20:09:35 +00:00
Reid Kleckner de86482ce0 Update Clang for LLVM rename AttributeSet -> AttributeList
llvm-svn: 298394
2017-03-21 16:57:30 +00:00
Vedant Kumar 129edab125 Retry: [ubsan] Detect UB loads from bitfields
It's possible to load out-of-range values from bitfields backed by a
boolean or an enum. Check for UB loads from bitfields.

This is the motivating example:

  struct S {
    BOOL b : 1; // Signed ObjC BOOL.
  };

  S s;
  s.b = 1; // This is actually stored as -1.
  if (s.b == 1) // Evaluates to false, -1 != 1.
    ...

Changes since the original commit:

- Single-bit bools are a special case (see CGF::EmitFromMemory), and we
  can't avoid dealing with them when loading from a bitfield. Don't try to
  insert a check in this case.

Differential Revision: https://reviews.llvm.org/D30423

llvm-svn: 297389
2017-03-09 16:06:27 +00:00
Vedant Kumar 3dea91fec6 Revert "[ubsan] Detect UB loads from bitfields"
This reverts commit r297298. It breaks the self-host on this bot:

  http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/962/steps/build%20clang%2Fubsan/logs/stdio

llvm-svn: 297331
2017-03-09 00:18:53 +00:00
Vedant Kumar 5c13623a69 [ubsan] Detect UB loads from bitfields
It's possible to load out-of-range values from bitfields backed by a
boolean or an enum. Check for UB loads from bitfields.

This is the motivating example:

  struct S {
    BOOL b : 1; // Signed ObjC BOOL.
  };

  S s;
  s.b = 1; // This is actually stored as -1.
  if (s.b == 1) // Evaluates to false, -1 != 1.
    ...

Differential Revision: https://reviews.llvm.org/D30423

llvm-svn: 297298
2017-03-08 17:38:57 +00:00
Reid Kleckner 092d065265 Don't assume cleanup emission preserves dominance in expr evaluation
Summary:
Because of the existence branches out of GNU statement expressions, it
is possible that emitting cleanups for a full expression may cause the
new insertion point to not be dominated by the result of the inner
expression. Consider this example:

  struct Foo { Foo(); ~Foo(); int x; };
  int g(Foo, int);
  int f(bool cond) {
    int n = g(Foo(), ({ if (cond) return 0; 42; }));
    return n;
  }

Before this change, result of the call to 'g' did not dominate its use
in the store to 'n'. The early return exit from the statement expression
branches to a shared cleanup block, which ends in a switch between the
fallthrough destination (the assignment to 'n') or the function exit
block.

This change solves the problem by spilling and reloading expression
evaluation results when any of the active cleanups have branches.

I audited the other call sites of enterFullExpression, and they don't
appear to keep and Values live across the site of the cleanup, except in
ARC code. I wasn't able to create a test case for ARC that exhibits this
problem, though.

Reviewers: rjmccall, rsmith

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D30590

llvm-svn: 297084
2017-03-06 22:18:34 +00:00
Vedant Kumar 5a97265351 [ubsan] Factor out logic to emit a range check. NFC.
This is a readability improvement, but it will also help prep an
upcoming patch to detect UB loads from bitfields.

llvm-svn: 296374
2017-02-27 19:46:19 +00:00
Vedant Kumar e550d11d34 Rename a helper function, NFC.
llvm-svn: 295918
2017-02-23 01:22:38 +00:00
Vedant Kumar 34b1fd6aaa Retry^2: [ubsan] Reduce null checking of C++ object pointers (PR27581)
This patch teaches ubsan to insert exactly one null check for the 'this'
pointer per method/lambda.

Previously, given a load of a member variable from an instance method
('this->x'), ubsan would insert a null check for 'this', and another
null check for '&this->x', before allowing the load to occur.

Similarly, given a call to a method from another method bound to the
same instance ('this->foo()'), ubsan would a redundant null check for
'this'. There is also a redundant null check in the case where the
object pointer is a reference ('Ref.foo()').

This patch teaches ubsan to remove the redundant null checks identified
above.

Testing: check-clang, check-ubsan, and a stage2 ubsan build.

I also compiled X86FastISel.cpp with -fsanitize=null using
patched/unpatched clangs based on r293572. Here are the number of null
checks emitted:

  -------------------------------------
  | Setup          | # of null checks |
  -------------------------------------
  | unpatched, -O0 |            21767 |
  | patched, -O0   |            10758 |
  -------------------------------------

Changes since the initial commit:
- Don't introduce any unintentional object-size or alignment checks.
- Don't rely on IRGen of C labels in the test.

Differential Revision: https://reviews.llvm.org/D29530

llvm-svn: 295515
2017-02-17 23:22:59 +00:00
Vedant Kumar 18348ea9b9 [ubsan] Pass a set of checks to skip to EmitTypeCheck() (NFC)
CodeGenFunction::EmitTypeCheck accepts a bool flag which controls
whether or not null checks are emitted. Make this a bit more flexible by
changing the bool to a SanitizerSet.

Needed for an upcoming change which deals with a scenario in which we
only want to emit null checks.

llvm-svn: 295514
2017-02-17 23:22:55 +00:00
Vedant Kumar 29ba8d9bfe Revert "Retry: [ubsan] Reduce null checking of C++ object pointers (PR27581)"
This reverts commit r295401. It breaks the ubsan self-host. It inserts
object size checks once per C++ method which fire when the structure is
empty.

llvm-svn: 295494
2017-02-17 20:59:40 +00:00
Vedant Kumar 55875b9955 Retry: [ubsan] Reduce null checking of C++ object pointers (PR27581)
This patch teaches ubsan to insert exactly one null check for the 'this'
pointer per method/lambda.

Previously, given a load of a member variable from an instance method
('this->x'), ubsan would insert a null check for 'this', and another
null check for '&this->x', before allowing the load to occur.

Similarly, given a call to a method from another method bound to the
same instance ('this->foo()'), ubsan would a redundant null check for
'this'. There is also a redundant null check in the case where the
object pointer is a reference ('Ref.foo()').

This patch teaches ubsan to remove the redundant null checks identified
above.

Testing: check-clang and check-ubsan. I also compiled X86FastISel.cpp
with -fsanitize=null using patched/unpatched clangs based on r293572.
Here are the number of null checks emitted:

  -------------------------------------
  | Setup          | # of null checks |
  -------------------------------------
  | unpatched, -O0 |            21767 |
  | patched, -O0   |            10758 |
  -------------------------------------

Changes since the initial commit: don't rely on IRGen of C labels in the
test.

Differential Revision: https://reviews.llvm.org/D29530

llvm-svn: 295401
2017-02-17 02:03:51 +00:00
Vedant Kumar 4f94a94bea Revert "[ubsan] Reduce null checking of C++ object pointers (PR27581)"
This reverts commit r295391. It breaks this bot:

http://lab.llvm.org:8011/builders/clang-with-thin-lto-ubuntu/builds/1898

I need to not rely on labels in the IR test.

llvm-svn: 295396
2017-02-17 01:42:36 +00:00
Vedant Kumar 3e5a9a6be8 [ubsan] Reduce null checking of C++ object pointers (PR27581)
This patch teaches ubsan to insert exactly one null check for the 'this'
pointer per method/lambda.

Previously, given a load of a member variable from an instance method
('this->x'), ubsan would insert a null check for 'this', and another
null check for '&this->x', before allowing the load to occur.

Similarly, given a call to a method from another method bound to the
same instance ('this->foo()'), ubsan would a redundant null check for
'this'. There is also a redundant null check in the case where the
object pointer is a reference ('Ref.foo()').

This patch teaches ubsan to remove the redundant null checks identified
above.

Testing: check-clang and check-ubsan. I also compiled X86FastISel.cpp
with -fsanitize=null using patched/unpatched clangs based on r293572.
Here are the number of null checks emitted:

  -------------------------------------
  | Setup          | # of null checks |
  -------------------------------------
  | unpatched, -O0 |            21767 |
  | patched, -O0   |            10758 |
  -------------------------------------

Differential Revision: https://reviews.llvm.org/D29530

llvm-svn: 295391
2017-02-17 01:05:42 +00:00
Filipe Cabecinhas fe5e5afd53 [ubsan] Minimize size of data for type_mismatch (Redo of D19667)
Summary:
This patch makes the type_mismatch static data 7 bytes smaller (and it
ends up being 16 bytes smaller due to alignment restrictions, at least
on some x86-64 environments).

It revs up the type_mismatch handler version since we're breaking binary
compatibility. I will soon post a patch for the compiler-rt side.

Reviewers: rsmith, kcc, vitalybuka, pgousseau, gbedwell

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28242

llvm-svn: 291236
2017-01-06 14:40:12 +00:00
Egor Churaev 89831421af Fix problems in "[OpenCL] Enabling the usage of CLK_NULL_QUEUE as compare operand."
Summary: Fixed warnings in commit: https://reviews.llvm.org/rL290171

Reviewers: djasper, Anastasia

Subscribers: yaxunl, cfe-commits, bader

Differential Revision: https://reviews.llvm.org/D27981

llvm-svn: 290431
2016-12-23 14:55:49 +00:00
Saleem Abdulrasool 05b8fde8ee CodeGen: ubsan is built static on windows, give handlers local storage
The UBSAN runtime is built static on Windows.  This requires that we give local
storage always.  This impacts Windows where the linker would otherwise have to
generate a thunk to access the symbol via the IAT.  This should repair the
windows clang build bots.

llvm-svn: 289829
2016-12-15 16:30:20 +00:00
Saleem Abdulrasool ca6e2b4876 CodeGen: clean up -Wpedantic warning (NFC)
lib/CodeGen/CGExpr.cpp:2511:2: warning: extra ';' [-Wpedantic]
   };
    ^

Clean up warning from gcc 6.

llvm-svn: 289514
2016-12-13 03:27:35 +00:00
Vedant Kumar 4881bdf141 Avoid use of std::to_string. NFC.
Apparently this routine isn't available on some Android platforms. See
the mailing list thread re: D21695.

llvm-svn: 289452
2016-12-12 18:47:33 +00:00
Filipe Cabecinhas 84171bd476 [Fix] Add missing include from r289444.
llvm-svn: 289446
2016-12-12 16:43:40 +00:00
Filipe Cabecinhas 322ecd901b [clang] Version support for UBSan handlers
This adds a way for us to version any UBSan handler by itself.
The patch overrides D21289 for a better implementation (we're able to
rev up a single handler).

After this, then we can land a slight modification of D19667+D19668.

We probably don't want to keep all the versions in compiler-rt (maybe we
want to deprecate on one release and remove the old handler on the next
one?), but with this patch we will loudly fail to compile when mixing
incompatible handler calls, instead of silently compiling and then
providing bad error messages.

Reviewers: kcc, samsonov, rsmith, vsk

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D21695

llvm-svn: 289444
2016-12-12 16:18:40 +00:00
Vedant Kumar 4593a46cd9 [ubsan] Treat ObjC's BOOL as if its range is always {0, 1}
On some Apple platforms, the ObjC BOOL type is defined as a signed char.
When performing instrumentation for -fsanitize=bool, we'd like to treat
the range of BOOL like it's always {0, 1}. While we can't change clang's
IRGen for char-backed BOOL's due to ABI compatibility concerns, we can
teach ubsan to catch potential abuses of this type.

rdar://problem/29502773

Differential Revision: https://reviews.llvm.org/D27607

llvm-svn: 289290
2016-12-09 23:48:18 +00:00
Richard Smith 122f88d481 [c++17] P0135R1: Guaranteed copy elision.
When an object of class type is initialized from a prvalue of the same type
(ignoring cv qualifications), use the prvalue to initialize the object directly
instead of inserting a redundant elidable call to a copy constructor.

llvm-svn: 288866
2016-12-06 23:52:28 +00:00
Mehdi Amini dc9bf8fab6 Improve handling of __FUNCTION__ and other predefined expression for Objective-C Blocks
Instead of always displaying the mangled name, try to do better
and get something closer to regular functions.

Recommit r287039 (that was reverted in r287039) with a tweak to
be more generic, and test fixes!

Differential Revision: https://reviews.llvm.org/D26522

llvm-svn: 287085
2016-11-16 07:07:28 +00:00
Mehdi Amini f5f37ee546 Revert "Improve handling of __FUNCTION__ and other predefined expression for Objective-C Blocks"
This reverts commit r287039, tests are broken.

llvm-svn: 287043
2016-11-15 22:19:50 +00:00
Mehdi Amini 26168ad5c5 Improve handling of __FUNCTION__ and other predefined expression for Objective-C Blocks
Instead of always displaying the mangled name, try to do better
and get something closer to regular functions.

Differential Revision: https://reviews.llvm.org/D26522

llvm-svn: 287039
2016-11-15 21:47:11 +00:00
Alexey Bataev 611b0a11df [OPENMP] Fixed codegen for __real/__imag expressions in atomic
constructs.

For __real/__imag unary expressions clang emits lvalue with the
associated type from the original complex expression, but not the
underlying builtin integer or float type. This causes crash in codegen
for atomic constructs, if __real/__imag expression are used in atomic
  constructs.

llvm-svn: 286129
2016-11-07 18:15:02 +00:00
Alexey Bataev ac5eabb0b9 [OPENMP] Fixed capturing of VLA variables.
After some changes in codegen capturing of VLA variables in OpenMP regions was broken, causing compiler crash. Patch fixes this issue.

llvm-svn: 286103
2016-11-07 11:16:04 +00:00
Diana Picus 1e2b7e6672 Revert "[OPENMP] Fixed capturing of VLA variables."
This reverts commit r286098 because the modified test breaks on many of the
buildbots.

llvm-svn: 286102
2016-11-07 10:01:43 +00:00
Alexey Bataev 420537fad8 [OPENMP] Fixed capturing of VLA variables.
After some changes in codegen capturing of VLA variables in OpenMP
regions was broken, causing compiler crash. Patch fixes this issue.

llvm-svn: 286098
2016-11-07 08:07:25 +00:00
John McCall b92ab1afd5 Refactor call emission to package the function pointer together with
abstract information about the callee.  NFC.

The goal here is to make it easier to recognize indirect calls and
trigger additional logic in certain cases.  That logic will come in
a later patch; in the meantime, I felt that this was a significant
improvement to the code.

llvm-svn: 285258
2016-10-26 23:46:34 +00:00
Akira Hatanaka 642f799b0d [CodeGen][ObjC] Do not call objc_storeStrong when initializing a
constexpr variable.

When compiling a constexpr NSString initialized with an objective-c
string literal, CodeGen emits objc_storeStrong on an uninitialized
alloca, which causes a crash.

This patch folds the code in EmitScalarInit into EmitStoreThroughLValue
and fixes the crash by calling objc_retain on the string instead of
using objc_storeStrong.

rdar://problem/28562009

Differential Revision: https://reviews.llvm.org/D25547

llvm-svn: 284516
2016-10-18 19:05:41 +00:00
Vedant Kumar e356f1a50c [ubsan] Disable bounds-check for flexible array ivars
This eliminates a class of false positives for -fsanitize=array-bounds
on instrumented ObjC projects.

Differential Revision: https://reviews.llvm.org/D22227

llvm-svn: 283249
2016-10-04 20:36:04 +00:00
Richard Smith a560ccf2af Switch to a different workaround for unimplementability of P0145R3 in MS ABIs.
Instead of ignoring the evaluation order rule, ignore the "destroy parameters
in reverse construction order" rule for the small number of problematic cases.
This only causes incorrect behavior in the rare case where both parameters to
an overloaded operator <<, >>, ->*, &&, ||, or comma are of class type with
non-trivial destructor, and the program is depending on those parameters being
destroyed in reverse construction order.

We could do a little better here by reversing the order of parameter
destruction for those functions (and reversing the argument evaluation order
for all direct calls, not just those with operator syntax), but that is not a
complete solution to the problem, as the same situation can be reached by an
indirect function call.

Approach reviewed off-line by rnk.

llvm-svn: 282777
2016-09-29 21:30:12 +00:00
Richard Smith 762672a73a Re-commit r282556, reverted in r282564, with a fix to CallArgList::addFrom to
function correctly when targeting MS ABIs (this appears to have never mattered
prior to this change).

Update test case to always cover both 32-bit and 64-bit Windows ABIs, since
they behave somewhat differently from each other here.

Update test case to also cover operators , && and ||, which it appears are also
affected by P0145R3 (they're not explicitly called out by the design document,
but this is the emergent behavior of the existing wording).


Original commit message:

P0145R3 (C++17 evaluation order tweaks): evaluate the right-hand side of
assignment and compound-assignment operators before the left-hand side. (Even
if it's an overloaded operator.)

This completes the implementation of P0145R3 + P0400R0 for all targets except
Windows, where the evaluation order guarantees for <<, >>, and ->* are
unimplementable as the ABI requires the function arguments are evaluated from
right to left (because parameter destructors are run from left to right in the
callee).

llvm-svn: 282619
2016-09-28 19:09:10 +00:00
Richard Smith 4499145a5f Revert r282556. This change made several bots unhappy.
llvm-svn: 282564
2016-09-28 02:20:06 +00:00
Richard Smith 97a616d624 P0145R3 (C++17 evaluation order tweaks): evaluate the right-hand side of
assignment and compound-assignment operators before the left-hand side. (Even
if it's an overloaded operator.)

This completes the implementation of P0145R3 + P0400R0 for all targets except
Windows, where the evaluation order guarantees for <<, >>, and ->* are
unimplementable as the ABI requires the function arguments are evaluated from
right to left (because parameter destructors are run from left to right in the
callee).

llvm-svn: 282556
2016-09-27 23:44:22 +00:00
Richard Smith 4088571c51 Remove default argument from lambda to appease old MSVC.
llvm-svn: 282464
2016-09-27 00:53:24 +00:00
Richard Smith 9e67b9922b P0145R3 (C++17 evaluation order tweaks): consistently emit the LHS of array
subscripting before the RHS, regardless of which is the base and which is the
index.

llvm-svn: 282453
2016-09-26 23:49:47 +00:00
Peter Collingbourne eeb56abe64 Update Clang for D20147 ("DebugInfo: New metadata representation for global variables.")
Differential Revision: http://reviews.llvm.org/D20415

llvm-svn: 281285
2016-09-13 01:13:19 +00:00
Amaury Sechet 21f51b3a32 Update clang for D21514. NFC
Summary: As per title.

Reviewers: ahatanak, bkramer, whitequark, mehdi_amini, void

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D21515

llvm-svn: 281018
2016-09-09 04:42:49 +00:00
Richard Smith da38363784 P0217R3: code generation support for decomposition declarations.
llvm-svn: 278642
2016-08-15 01:33:41 +00:00
Yaxun Liu 0bc4b2d337 [OpenCL] Generate opaque type for sampler_t and function call for the initializer
Currently Clang use int32 to represent sampler_t, which have been a source of issue for some backends, because in some backends sampler_t cannot be represented by int32. They have to depend on kernel argument metadata and use IPA to find the sampler arguments and global variables and transform them to target specific sampler type.

This patch uses opaque pointer type opencl.sampler_t* for sampler_t. For each use of file-scope sampler variable, it generates a function call of __translate_sampler_initializer. For each initialization of function-scope sampler variable, it generates a function call of __translate_sampler_initializer.

Each builtin library can implement its own __translate_sampler_initializer(). Since the real sampler type tends to be architecture dependent, allowing it to be initialized by a library function simplifies backend design. A typical implementation of __translate_sampler_initializer could be a table lookup of real sampler literal values. Since its argument is always a literal, the returned pointer is known at compile time and easily optimized to finally become some literal values directly put into image read instructions.

This patch is partially based on Alexey Sotkin's work in Khronos Clang (3d4eec6162).

Differential Revision: https://reviews.llvm.org/D21567

llvm-svn: 277024
2016-07-28 19:26:30 +00:00
Craig Topper f2f1a099a7 [CodeGen] Use llvm::Type::getVectorNumElements instead of casting to llvm::VectorType and calling getNumElements. This is equivalent and shorter.
llvm-svn: 274823
2016-07-08 02:17:35 +00:00
Tim Shen 421119fd89 [Temporary, Lifetime] Add lifetime marks for temporaries
With all MaterializeTemporaryExprs coming with a ExprWithCleanups, it's
easy to add correct lifetime.end marks into the right RunCleanupsScope.

Differential Revision: http://reviews.llvm.org/D20499

llvm-svn: 274385
2016-07-01 21:08:47 +00:00
Peter Collingbourne 8dd14da0dc CodeGen: Update Clang to use the new type metadata.
Differential Revision: http://reviews.llvm.org/D21054

llvm-svn: 273730
2016-06-24 21:21:46 +00:00
Peter Collingbourne bcf909d737 Update clang for D20348
Differential Revision: http://reviews.llvm.org/D20339

llvm-svn: 272710
2016-06-14 21:02:05 +00:00
David Majnemer a38c9f1fa5 [MS Volatile] Don't make volatile loads/stores to underaligned objects atomic
Underaligned atomic LValues require libcalls which MSVC doesn't have.
MSVC doesn't seem to consider such operations as requiring a barrier
anyway.

This fixes PR27843.

llvm-svn: 270576
2016-05-24 16:09:25 +00:00
Akira Hatanaka fdacb5c056 [ObjC][CodeGen] Remove an assert that is no longer correct.
clang asserts when compiling the following code because r231508 made
changes to promote constant temporary arrays and records to globals
with constant initializers:

std::vector<NSString*> strs = {@"a", @"b"};

This commit changes the code to return early if the object returned by
createReferenceTemporary is a global variable with an initializer.

rdar://problem/25504992
rdar://problem/25955179

Differential Revision: http://reviews.llvm.org/D20045

llvm-svn: 269385
2016-05-13 01:21:23 +00:00
Filipe Cabecinhas ab731f7e86 [ubsan] Add -fsanitize-undefined-strip-path-components=N
Summary:
This option allows the user to control how much of the file name is
emitted by UBSan. Tuning this option allows one to save space in the
resulting binary, which is helpful for restricted execution
environments.

With a positive N, UBSan skips the first N path components.
With a negative N, UBSan only keeps the last N path components.

Reviewers: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D19666

llvm-svn: 269309
2016-05-12 16:51:36 +00:00
Reid Kleckner 9d03109233 Fix argument expansion of reference fields of structs
r268261 made Clang "expand" more struct arguments on Windows. It removed
the check for 'RD->isCLike()', which was preventing us from attempting
to expand structs with reference type fields.

Our expansion code was attempting to load and pass each field of the
type in turn. We were accidentally doing one to many loads on reference
type fields.

On the function prologue side, we can use
EmitLValueForFieldInitialization, which obviously gets the address of
the field. On the call side, I tweaked EmitRValueForField directly,
since this is the only use of this method.

Fixes PR27607

llvm-svn: 268321
2016-05-02 22:42:34 +00:00
Benjamin Kramer 5ff6747e04 Remove redundant conditions of the form (A || (!A && B)) -> (A || B)
Found by cppcheck! PR27286 PR27287 PR27288 PR27289

llvm-svn: 265918
2016-04-11 08:26:13 +00:00
Saleem Abdulrasool 10a4972a8d revert SVN r265702, r265640
Revert the two changes to thread CodeGenOptions into the TargetInfo allocation
and to fix the layering violation by moving CodeGenOptions into Basic.
Code Generation is arguably not particularly "basic".  This addresses Richard's
post-commit review comments.  This change purely does the mechanical revert and
will be followed up with an alternate approach to thread the desired information
into TargetInfo.

llvm-svn: 265806
2016-04-08 16:52:00 +00:00
Saleem Abdulrasool 94cfc603d1 Basic: move CodeGenOptions from Frontend
This is a mechanical move of CodeGenOptions from libFrontend to libBasic.  This
fixes the layering violation introduced earlier by threading CodeGenOptions into
TargetInfo.  It should also fix the modules based self-hosting builds.  NFC.

llvm-svn: 265702
2016-04-07 17:49:44 +00:00
Evgeniy Stepanov 02279ed12d [cfi] Don't emit checks for disabled CFI kinds.
In the cross-DSO CFI mode clang emits __cfi_check_fail that handles
errors triggered from other modules with targets in the current
module. With this change, __cfi_check_fail will handle errors for
CFI kinds that are not enabled in the current module as if they
have the trapping behaviour (-fsanitize-trap=...).

This fixes a bug where some combinations of -fsanitize* flags may
result in a link failure due to a missing sanitizer runtime library
for the diagnostic calls in __cfi_check_fail.

llvm-svn: 263578
2016-03-15 20:19:29 +00:00
Mehdi Amini 557c20a886 Remove compile time PreserveName in favor of a runtime cc1 -discard-value-names option
Summary:
This flag is enabled by default in the driver when NDEBUG is set. It
is forwarded on the LLVMContext to discard all value names (but
GlobalValue) for performance purpose.

This an improved version of D18024

Reviewers: echristo, chandlerc

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D18127

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263394
2016-03-13 21:05:23 +00:00
Eric Christopher 02e3dd4b2e Temporarily revert these patches:
commit 60d9845f6a037122d9be9a6d92d4de617ef45b04
Author: Mehdi Amini <mehdi.amini@apple.com>
Date:   Fri Mar 11 18:48:02 2016 +0000

    Fix clang crash: when CodeGenAction is initialized without a
    context, use the member and not the parameter

    From: Mehdi Amini <mehdi.amini@apple.com>

    git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@263273
    91177308-0d34-0410-b5e6-96231b3b80d8

commit af7ce3bf04a75ad5124b457b805df26006bd215b
Author: Mehdi Amini <mehdi.amini@apple.com>
Date:   Fri Mar 11 17:32:58 2016 +0000

    Fix build: use -> with pointers and not .

    Silly typo.

    From: Mehdi Amini <mehdi.amini@apple.com>

    git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@263267
    91177308-0d34-0410-b5e6-96231b3b80d8

commit d0eea119192814954e7368c77d0dc5a9eeec1fbb
Author: Mehdi Amini <mehdi.amini@apple.com>
Date:   Fri Mar 11 17:15:44 2016 +0000

    Remove compile time PreserveName switch based on NDEBUG

    Summary:
    Following r263086, we are now relying on a flag on the Context to
    discard Value names in release builds.

    Reviewers: chandlerc

    Subscribers: cfe-commits

    Differential Revision: http://reviews.llvm.org/D18024

    From: Mehdi Amini <mehdi.amini@apple.com>

    git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@263257
    91177308-0d34-0410-b5e6-96231b3b80d8

until we can fix the Release builds.

This reverts commits 263257, 263267, 263273

llvm-svn: 263320
2016-03-12 01:47:11 +00:00
Mehdi Amini e803fc3276 Remove compile time PreserveName switch based on NDEBUG
Summary:
Following r263086, we are now relying on a flag on the Context to
discard Value names in release builds.

Reviewers: chandlerc

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D18024

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263257
2016-03-11 17:15:44 +00:00
John McCall c56a8b3284 Preserve ExtParameterInfos into CGFunctionInfo.
As part of this, make the function-arrangement interfaces
a little simpler and more semantic.

NFC.

llvm-svn: 263191
2016-03-11 04:30:31 +00:00
Alexey Bataev 31300ed0a5 [OPENMP 4.0] Fixed support of array sections/array subscripts.
Codegen for array sections/array subscripts worked only for expressions with arrays as base. Patch fixes codegen for bases with pointer/reference types.

llvm-svn: 259776
2016-02-04 11:27:03 +00:00
Evgeniy Stepanov f31ea30694 [cfi] Safe handling of unaddressable vtable pointers (clang).
Avoid crashing when printing diagnostics for vtable-related CFI
errors. In diagnostic mode, the frontend does an additional check of
the vtable pointer against the set of all known vtable addresses and
lets the runtime handler know if it is safe to inspect the vtable.

http://reviews.llvm.org/D16823

llvm-svn: 259716
2016-02-03 22:18:55 +00:00
Evgeniy Stepanov 4d3b087c93 Fix use of constexpr std::pair that's not in C++11.
llvm-svn: 258749
2016-01-25 23:45:37 +00:00
Evgeniy Stepanov 3fd61df186 [cfi] Cross-DSO CFI diagnostic mode (clang part)
* Runtime diagnostic data for cfi-icall changed to match the rest of
  cfi checks
* Layout of all CFI diagnostic data changed to put Kind at the
  beginning. There is no ABI stability promise yet.
* Call cfi_slowpath_diag instead of cfi_slowpath when needed.
* Emit __cfi_check_fail function, which dispatches a CFI check
  faliure according to trap/recover settings of the current module.
* A tiny driver change to match the way the new handlers are done in
  compiler-rt.

llvm-svn: 258745
2016-01-25 23:34:52 +00:00
Peter Collingbourne dc13453128 Introduce -fsanitize-stats flag.
This is part of a new statistics gathering feature for the sanitizers.
See clang/docs/SanitizerStats.rst for further info and docs.

Differential Revision: http://reviews.llvm.org/D16175

llvm-svn: 257971
2016-01-16 00:31:22 +00:00
Peter Collingbourne 574975efa9 CodeGen: Only emit CFI unrelated cast checks for bit casts.
We were previously emitting them for no-op casts (e.g. implicit casts
to const).

llvm-svn: 257738
2016-01-14 02:49:48 +00:00
George Burgess IV df1ed0099b [Bugfix] Fix ICE on constexpr vector splat.
In {CG,}ExprConstant.cpp, we weren't treating vector splats properly.
This patch makes us treat splats more properly.

Additionally, this patch adds a new cast kind which allows a bool->int
cast to result in -1 or 0, instead of 1 or 0 (for true and false,
respectively), so we can sanely model OpenCL bool->int casts in the AST.

Differential Revision: http://reviews.llvm.org/D14877

llvm-svn: 257559
2016-01-13 01:52:39 +00:00
Evgeniy Stepanov fd6f92d5cb Cross-DSO control flow integrity (Clang part).
Clang-side cross-DSO CFI.

* Adds a command line flag -f[no-]sanitize-cfi-cross-dso.
* Links a runtime library when enabled.
* Emits __cfi_slowpath calls is bitset test fails.
* Emits extra hash-based bitsets for external CFI checks.
* Sets a module flag to enable __cfi_check generation during LTO.

This mode does not yet support diagnostics.

llvm-svn: 255694
2015-12-15 23:00:20 +00:00
Samuel Antao 798f11cfb7 Preserve exceptions information during calls code generation.
This patch changes the generation of CGFunctionInfo to contain 
the FunctionProtoType if it is available. This enables the code 
generation for call instructions to look into this type for 
exception information and therefore generate better quality 
IR - it will not create invoke instructions for functions that 
are know not to throw.

llvm-svn: 253926
2015-11-23 22:04:44 +00:00
Eric Christopher 39db726093 Clarify and elaborate the conditions on which we're checking target
features for calls.

llvm-svn: 253117
2015-11-14 01:56:04 +00:00
Eric Christopher 2b2d56f059 Provide a frontend based error for always_inline functions that require
target features that the caller function doesn't provide. This matches
the existing backend failure to inline functions that don't have
matching target features - and diagnoses earlier in the case of
always_inline.

Fix up a few test cases that were, in fact, invalid if you tried
to generate code from the backend with the specified target features
and add a couple of tests to illustrate what's going on.

This should fix PR25246.

llvm-svn: 252834
2015-11-12 00:44:12 +00:00
Duncan P. N. Exon Smith 9f5260ab13 CodeGen: Remove implicit ilist iterator conversions, NFC
Make ilist iterator conversions explicit in clangCodeGen.  Eventually
I'll remove them everywhere.

llvm-svn: 252358
2015-11-06 23:00:41 +00:00
John McCall 460ce58fa6 Define weak and __weak to mean ARC-style weak references, even in MRC.
Previously, __weak was silently accepted and ignored in MRC mode.
That makes this a potentially source-breaking change that we have to
roll out cautiously.  Accordingly, for the time being, actual support
for __weak references in MRC is experimental, and the compiler will
reject attempts to actually form such references.  The intent is to
eventually enable the feature by default in all non-GC modes.
(It is, of course, incompatible with ObjC GC's interpretation of
__weak.)

If you like, you can enable this feature with
  -Xclang -fobjc-weak
but like any -Xclang option, this option may be removed at any point,
e.g. if/when it is eventually enabled by default.

This patch also enables the use of the ARC __unsafe_unretained qualifier
in MRC.  Unlike __weak, this is being enabled immediately.  Since
variables are essentially __unsafe_unretained by default in MRC,
the only practical uses are (1) communication and (2) changing the
default behavior of by-value block capture.

As an implementation matter, this means that the ObjC ownership
qualifiers may appear in any ObjC language mode, and so this patch
removes a number of checks for getLangOpts().ObjCAutoRefCount
that were guarding the processing of these qualifiers.  I don't
expect this to be a significant drain on performance; it may even
be faster to just check for these qualifiers directly on a type
(since it's probably in a register anyway) than to do N dependent
loads to grab the LangOptions.

rdar://9674298

llvm-svn: 251041
2015-10-22 18:38:17 +00:00
Alexey Bataev 2bf9b4c0d1 [DEBUG INFO] Emit debug info for type used in explicit cast only.
Currently debug info for types used in explicit cast only is not emitted. It happened after a patch for better alignment handling. This patch fixes this bug.
Differential Revision: http://reviews.llvm.org/D13582

llvm-svn: 250795
2015-10-20 04:24:12 +00:00
John McCall 8460bcaa33 Honor the casted-to alignment of an explicit cast even when
Sema thinks the cast is a no-op, as it does when (e.g.) the
only thing that changes is an alignment attribute.

Fixed PR24944.

llvm-svn: 248775
2015-09-29 04:37:40 +00:00
Piotr Padlewski 4b1ac72cd4 Decorating vptr load & stores with !invariant.group
Adding !invariant.group to vptr load/stores for devirtualization purposes.
For more goto:
http://lists.llvm.org/pipermail/cfe-dev/2015-July/044227.html

http://reviews.llvm.org/D12026

llvm-svn: 247725
2015-09-15 21:46:55 +00:00
Alexey Bataev c71a4099cf [OPENMP] Preserve alignment of the original variables for the captured references.
Patch makes codegen to preserve alignment of the shared variables captured and used in OpenMP regions.

llvm-svn: 247401
2015-09-11 10:29:41 +00:00