Commit Graph

734 Commits

Author SHA1 Message Date
Ivan A. Kosarev 6fa20cfea3 [CodeGen] Unify generation of scalar and struct-path TBAA tags
This patch makes it possible to produce access tags in a uniform
manner regardless whether the resulting tag will be a scalar or a
struct-path one. getAccessTagInfo() now takes care of the actual
translation of access descriptors to tags and can handle all
kinds of accesses. Facilities that specific to scalar accesses
are eliminated.

Some more details:
* DecorateInstructionWithTBAA() is not responsible for conversion
  of types to access tags anymore. Instead, it takes an access
  descriptor (TBAAAccessInfo) and generates corresponding access
  tag from it.
* getTBAAInfoForVTablePtr() reworked to
  getTBAAVTablePtrAccessInfo() that now returns the
  virtual-pointer access descriptor and not the virtual-point
  type metadata.
* Added function getTBAAMayAliasAccessInfo() that returns the
  descriptor for may-alias accesses.
* getTBAAStructTagInfo() renamed to getTBAAAccessTagInfo() as now
  it is the only way to generate access tag by a given access
  descriptor. It is capable of producing both scalar and
  struct-path tags, depending on options and availability of the
  base access type. getTBAAScalarTagInfo() and its cache
  ScalarTagMetadataCache are eliminated.
* Now that we do not need to care about whether the resulting
  access tag should be a scalar or struct-path one,
  getTBAAStructTypeInfo() is renamed to getBaseTypeInfo().
* Added function getTBAAAccessInfo() that constructs access
  descriptor by a given QualType access type.

This is part of D37826 reworked to be a separate patch to
simplify review.

Differential Revision: https://reviews.llvm.org/D38503

llvm-svn: 314977
2017-10-05 10:47:51 +00:00
Ivan A. Kosarev 289574edc0 [CodeGen] Do not refer to complete TBAA info where we actually deal with just TBAA access types
This patch fixes misleading names of entities related to getting,
setting and generation of TBAA access type descriptors.

This is effectively an attempt to provide a review for D37826 by
breaking it into smaller pieces.

Differential Revision: https://reviews.llvm.org/D38404

llvm-svn: 314657
2017-10-02 09:54:47 +00:00
Vlad Tsyrklevich 2eccdab308 Allow specifying sanitizers in blacklists
Summary:
This is the follow-up patch to D37924.

This change refactors clang to use the the newly added section headers
in SpecialCaseList to specify which sanitizers blacklists entries
should apply to, like so:

  [cfi-vcall]
  fun:*bad_vcall*
  [cfi-derived-cast|cfi-unrelated-cast]
  fun:*bad_cast*

The SanitizerSpecialCaseList class has been added to allow querying by
SanitizerMask, and SanitizerBlacklist and its downstream users have been
updated to provide that information. Old blacklists not using sections
will continue to function identically since the blacklist entries will
be placed into a '[*]' section by default matching against all
sanitizers.

Reviewers: pcc, kcc, eugenis, vsk

Reviewed By: eugenis

Subscribers: dberris, cfe-commits, mgorny

Differential Revision: https://reviews.llvm.org/D37925

llvm-svn: 314171
2017-09-25 22:11:12 +00:00
Vedant Kumar bb5d485cd3 [ubsan] Function Sanitizer: Don't require writable text segments
This change will make it possible to use -fsanitize=function on Darwin and
possibly on other platforms. It fixes an issue with the way RTTI is stored into
function prologue data.

On Darwin, addresses stored in prologue data can't require run-time fixups and
must be PC-relative. Run-time fixups are undesirable because they necessitate
writable text segments, which can lead to security issues. And absolute
addresses are undesirable because they break PIE mode.

The fix is to create a private global which points to the RTTI, and then to
encode a PC-relative reference to the global into prologue data.

Differential Revision: https://reviews.llvm.org/D37597

llvm-svn: 313096
2017-09-13 00:04:35 +00:00
Dehao Chen 5e97f23441 Expose -mllvm -accurate-sample-profile to clang.
Summary: With accurate sample profile, we can do more aggressive size optimization. For some size-critical application, this can reduce the text size by 20%

Reviewers: davidxl, rsmith

Reviewed By: davidxl, rsmith

Subscribers: mehdi_amini, eraman, sanjoy, cfe-commits

Differential Revision: https://reviews.llvm.org/D37091

llvm-svn: 311707
2017-08-24 21:37:33 +00:00
Richard Smith 376c28e296 [ubsan] PR34266: When sanitizing the 'this' value for a member function that happens to be a lambda call operator, use the lambda's 'this' pointer, not the captured enclosing 'this' pointer (if any).
Do not sanitize the 'this' pointer of a member call operator for a lambda with
no capture-default, since that call operator can legitimately be called with a
null this pointer from the static invoker function. Any actual call with a null
this pointer should still be caught in the caller (if it is being sanitized).

This reinstates r311589 (reverted in r311680) with the above fix.

llvm-svn: 311695
2017-08-24 20:10:33 +00:00
Adrian Prantl 1b6d8713e4 Revert "[ubsan] PR34266: When sanitizing the 'this' value for a member function that happens to be a lambda call operator, use the lambda's 'this' pointer, not the captured enclosing 'this' pointer (if any)."
This reverts commit r311589 because of bot breakage.
http://green.lab.llvm.org/green/job/clang-stage2-cmake-RgSan_check/4115/consoleFull#15752874848254eaf0-7326-4999-85b0-388101f2d404.

llvm-svn: 311680
2017-08-24 18:18:24 +00:00
Richard Smith e3a5e8f03d [ubsan] PR34266: When sanitizing the 'this' value for a member function that happens to be a lambda call operator, use the lambda's 'this' pointer, not the captured enclosing 'this' pointer (if any).
llvm-svn: 311589
2017-08-23 19:39:04 +00:00
Reid Kleckner 2d3c421f1c Clean up some lambda conversion operator code, NFC
We don't need special handling in CodeGenFunction::GenerateCode for
lambda block pointer conversion operators anymore. The conversion
operator emission code immediately calls back to the generic
EmitFunctionBody.

Rename EmitLambdaStaticInvokeFunction to EmitLambdaStaticInvokeBody for
better consistency with the other Emit*Body methods.

I'm preparing to do something about PR28299, which touches this code.

llvm-svn: 310145
2017-08-04 22:38:06 +00:00
Vlad Tsyrklevich 3f3aad235d Reland "CFI: blacklist STL allocate() from unrelated-casts"
Reland r310097 with a fix for a debug assertion in NamedDecl.getName()

Differential Revision: https://reviews.llvm.org/D36294

llvm-svn: 310132
2017-08-04 21:21:00 +00:00
Vlad Tsyrklevich bbe96e50f3 Revert "Reland "CFI: blacklist STL allocate() from unrelated-casts""
This reverts commit r310105.

llvm-svn: 310121
2017-08-04 20:37:49 +00:00
Vlad Tsyrklevich bf736037be Reland "CFI: blacklist STL allocate() from unrelated-casts"
Reland r310097 with a unit test fix for MS ABI build bots.

Differential Revision: https://reviews.llvm.org/D36294

llvm-svn: 310105
2017-08-04 19:50:39 +00:00
Vlad Tsyrklevich 3fed079f8c Revert "CFI: blacklist STL allocate() from unrelated-casts"
This reverts commit r310097.

llvm-svn: 310099
2017-08-04 19:17:16 +00:00
Vlad Tsyrklevich 44200125e9 CFI: blacklist STL allocate() from unrelated-casts
Summary:
Previously, STL allocators were blacklisted in compiler_rt's
cfi_blacklist.txt because they mandated a cast from void* to T* before
object initialization completed. This change moves that logic into the
front end because C++ name mangling supports a substitution compression
mechanism for symbols that makes it difficult to blacklist the mangled
symbol for allocate() using a regular expression.

Motivated by crbug.com/751385.

Reviewers: pcc, kcc

Reviewed By: pcc

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D36294

llvm-svn: 310097
2017-08-04 19:10:11 +00:00
Alexey Sotkin 7d7f0dc08b [OpenCL] Fix access qualifiers metadata for kernel arguments with typedef
Subscribers: cfe-commits, yaxunl, Anastasia

Differential Revision: https://reviews.llvm.org/D35420

llvm-svn: 309155
2017-07-26 18:49:54 +00:00
Vedant Kumar c34d343f15 [ubsan] Improve diagnostics for return value checks (clang)
This patch makes ubsan's nonnull return value diagnostics more precise,
which makes the diagnostics more useful when there are multiple return
statements in a function. Example:

1 |__attribute__((returns_nonnull)) char *foo() {
2 |  if (...) {
3 |    return expr_which_might_evaluate_to_null();
4 |  } else {
5 |    return another_expr_which_might_evaluate_to_null();
6 |  }
7 |} // <- The current diagnostic always points here!

runtime error: Null returned from Line 7, Column 2!
With this patch, the diagnostic would point to either Line 3, Column 5
or Line 5, Column 5.

This is done by emitting source location metadata for each return
statement in a sanitized function. The runtime is passed a pointer to
the appropriate metadata so that it can prepare and deduplicate reports.

Compiler-rt patch (with more tests): https://reviews.llvm.org/D34298

Differential Revision: https://reviews.llvm.org/D34299

llvm-svn: 306163
2017-06-23 21:32:38 +00:00
Manoj Gupta 162b40a850 [Clang] Handle interaction of -pg and no_instrument_function attribute.
Summary:
Disable generation of counting-function attribute if no_instrument_function
attribute is present in function.
Interaction between -pg and no_instrument_function is the desired behavior
and matches gcc as well.
This is required for fixing a crash in Linux kernel when function tracing
is enabled.

Fixes PR33515.

Reviewers: hfinkel, rengolin, srhines, hans

Reviewed By: hfinkel

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D34357

llvm-svn: 305728
2017-06-19 18:45:03 +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
Keno Fischer 41d4b4e588 [CGDebugInfo] Finalize SubPrograms when we're done with them
`GenerateVarArgsThunk` in `CGVTables` clones a function before the frontend
is done emitting the compilation unit. Because of the way that DIBuilder
works, this means that the attached subprogram had incomplete (temporary)
metadata. Cloning such metadata is semantically disallowed, but happened
to work anyway due to bugs in the cloning logic. rL304226 attempted to fix
up that logic, but in the process exposed the incorrect API use here and
had to be reverted. To be able to fix this, I added a new method to
DIBuilder in rL304467, to allow finalizing a subprogram independently
of the entire compilation unit. Use that here, in preparation of re-applying
rL304226.

Reviewers: aprantl, dblaikie
Differential Revision: https://reviews.llvm.org/D33705

llvm-svn: 304470
2017-06-01 21:14:03 +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
Xiuli Pan be6da4bbdb [OpenCL] Add intel_reqd_sub_group_size attribute support
Summary:
Add intel_reqd_sub_group_size attribute support as intel extension  cl_intel_required_subgroup_size from
https://www.khronos.org/registry/OpenCL/extensions/intel/cl_intel_required_subgroup_size.txt

Reviewers: Anastasia, bader, hfinkel, pxli168

Reviewed By: Anastasia, bader, pxli168

Subscribers: cfe-commits, yaxunl

Differential Revision: https://reviews.llvm.org/D30805

llvm-svn: 302125
2017-05-04 07:31:20 +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
Egor Churaev ba8b84d7fb [OpenCL] Do not generate "kernel_arg_type_qual" metadata for non-pointer args
Summary:
"kernel_arg_type_qual" metadata should contain const/volatile/restrict
tags only for pointer types to match the corresponding requirement of
the OpenCL specification.

OpenCL 2.0 spec 5.9.3 Kernel Object Queries:

CL_KERNEL_ARG_TYPE_VOLATILE is returned if the argument is a pointer
and the referenced type is declared with the volatile qualifier.
[...]
Similarly, CL_KERNEL_ARG_TYPE_CONST is returned if the argument is a
pointer and the referenced type is declared with the restrict or const
qualifier.
[...]
CL_KERNEL_ARG_TYPE_RESTRICT will be returned if the pointer type is
marked restrict.

Reviewers: Anastasia, cfe-commits

Reviewed By: Anastasia

Subscribers: bader, yaxunl

Differential Revision: https://reviews.llvm.org/D31321

llvm-svn: 299192
2017-03-31 10:14:52 +00:00
Benjamin Kramer 2a7d39dfe8 [msan] Turn off lifetime markers even when use after scope checking is on.
Since r299174 use after scope checking is on by default. Even though
msan doesn't check for use after scope it gets confused by the lifetime
markers emitted for it, making unit tests fail. This is covered by
ninja check-msan.

llvm-svn: 299191
2017-03-31 09:19:25 +00:00
Dean Michael Berris 835832d37a [XRay] Add -fxray-{always,never}-instrument= flags to clang
Summary:
The -fxray-always-instrument= and -fxray-never-instrument= flags take
filenames that are used to imbue the XRay instrumentation attributes
using a whitelist mechanism (similar to the sanitizer special cases
list). We use the same syntax and semantics as the sanitizer blacklists
files in the implementation.

As implemented, we respect the attributes that are already defined in
the source file (i.e. those that have the
[[clang::xray_{always,never}_instrument]] attributes) before applying
the always/never instrument lists.

Reviewers: rsmith, chandlerc

Subscribers: jfb, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D30388

llvm-svn: 299041
2017-03-30 00:29:36 +00:00
Vedant Kumar 42c17ec5ac [ubsan] Add a nullability sanitizer
Teach UBSan to detect when a value with the _Nonnull type annotation
assumes a null value. Call expressions, initializers, assignments, and
return statements are all checked.

Because _Nonnull does not affect IRGen, the new checks are disabled by
default. The new driver flags are:

  -fsanitize=nullability-arg      (_Nonnull violation in call)
  -fsanitize=nullability-assign   (_Nonnull violation in assignment)
  -fsanitize=nullability-return   (_Nonnull violation in return stmt)
  -fsanitize=nullability          (all of the above)

This patch builds on top of UBSan's existing support for detecting
violations of the nonnull attributes ('nonnull' and 'returns_nonnull'),
and relies on the compiler-rt support for those checks. Eventually we
will need to update the diagnostic messages in compiler-rt (there are
FIXME's for this, which will be addressed in a follow-up).

One point of note is that the nullability-return check is only allowed
to kick in if all arguments to the function satisfy their nullability
preconditions. This makes it necessary to emit some null checks in the
function body itself.

Testing: check-clang and check-ubsan. I also built some Apple ObjC
frameworks with an asserts-enabled compiler, and verified that we get
valid reports.

Differential Revision: https://reviews.llvm.org/D30762

llvm-svn: 297700
2017-03-14 01:56:34 +00:00
Roger Ferrer Ibanez 3fa38a14ac Honor __unaligned in codegen for declarations and expressions
This patch honors the unaligned type qualifier (currently available through he
keyword __unaligned and -fms-extensions) in CodeGen. In the current form the
patch affects declarations and expressions. It does not affect fields of
classes.

Differential Revision: https://reviews.llvm.org/D30166

llvm-svn: 297276
2017-03-08 14:00:44 +00:00
Dean Michael Berris 418da3fe80 [XRay] [clang] Allow logging the first argument of a function call.
Summary:
Functions with the "xray_log_args" attribute will tell LLVM to emit a special
XRay sled for compiler-rt to copy any call arguments to your logging handler.

Reviewers: dberris

Reviewed By: dberris

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D29704

llvm-svn: 296999
2017-03-06 07:08:21 +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 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
Reid Kleckner a858981c1d [MS] Fix C++ destructor thunk line info for a declaration
Sometimes the MS ABI needs to emit thunks for declarations that don't
have bodies. Destructor thunks make calls to inlinable functions, so
they need line info or LLVM will complain.

Fixes PR31893

llvm-svn: 294465
2017-02-08 16:09:32 +00:00
Nirav Dave 0c86ccf4b4 [X86] Teach Clang about -mfentry flag
Replace mcount calls with calls to fentry.

Reviewers: hfinkel, craig.topper

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D28001

llvm-svn: 293649
2017-01-31 17:00:35 +00:00
Richard Smith 600b5261c4 PR0091R3: Implement parsing support for using templates as types.
This change adds a new type node, DeducedTemplateSpecializationType, to
represent a type template name that has been used as a type. This is modeled
around AutoType, and shares a common base class for representing a deduced
placeholder type.

We allow deduced class template types in a few more places than the standard
does: in conditions and for-range-declarators, and in new-type-ids. This is
consistent with GCC and with discussion on the core reflector. This patch
does not yet support deduced class template types being named in typename
specifiers.

llvm-svn: 293207
2017-01-26 20:40:47 +00:00
Alexey Bataev 880d8605e3 [OPENMP] Fix for PR31643: Clang crashes when compiling code on Windows
with SEH and openmp

In some cituations (during codegen for Windows SEH constructs)
CodeGenFunction instance may have CurFn equal to nullptr. OpenMP related
code does not expect such situation during cleanup.

llvm-svn: 292590
2017-01-20 08:57:28 +00:00
Anna Zaks e43b4fc0ae [tsan] Do not report errors in __destroy_helper_block_
There is a synchronization point between the reference count of a block dropping to zero and it's destruction, which TSan does not observe. Do not report errors in the compiler-emitted block destroy method and everything called from it.

This is similar to https://reviews.llvm.org/D25857

Differential Revision: https://reviews.llvm.org/D28387

llvm-svn: 291868
2017-01-13 00:50:50 +00:00
Mehdi Amini 7f873070c4 Add a cc1 option to force disabling lifetime-markers emission from clang
Summary: This intended as a debugging/development flag only.

Differential Revision: https://reviews.llvm.org/D28385

llvm-svn: 291300
2017-01-06 23:18:09 +00:00
Alex Lorenz c1608f7f69 Add -f[no-]strict-return flag that can be used to avoid undefined behaviour
in non-void functions that fall off at the end without returning a value when
compiling C++.

Clang uses the new compiler flag to determine when it should treat control flow
paths that fall off the end of a non-void function as unreachable. If
-fno-strict-return is on, the code generator emits the ureachable and trap
IR only when the function returns either a record type with a non-trivial
destructor or another non-trivially copyable type.

The primary goal of this flag is to avoid treating falling off the end of a
non-void function as undefined behaviour. The burden of undefined behaviour
is placed on the caller instead: if the caller ignores the returned value then
the undefined behaviour is avoided. This kind of behaviour is useful in
several cases, e.g. when compiling C code in C++ mode.

rdar://13102603

Differential Revision: https://reviews.llvm.org/D27163

llvm-svn: 290960
2017-01-04 13:40:34 +00:00
Chandler Carruth fcd33149b4 Cleanup the handling of noinline function attributes, -fno-inline,
-fno-inline-functions, -O0, and optnone.

These were really, really tangled together:
- We used the noinline LLVM attribute for -fno-inline
  - But not for -fno-inline-functions (breaking LTO)
  - But we did use it for -finline-hint-functions (yay, LTO is happy!)
  - But we didn't for -O0 (LTO is sad yet again...)
- We had weird structuring of CodeGenOpts with both an inlining
  enumeration and a boolean. They interacted in weird ways and
  needlessly.
- A *lot* of set smashing went on with setting these, and then got worse
  when we considered optnone and other inlining-effecting attributes.
- A bunch of inline affecting attributes were managed in a completely
  different place from -fno-inline.
- Even with -fno-inline we failed to put the LLVM noinline attribute
  onto many generated function definitions because they didn't show up
  as AST-level functions.
- If you passed -O0 but -finline-functions we would run the normal
  inliner pass in LLVM despite it being in the O0 pipeline, which really
  doesn't make much sense.
- Lastly, we used things like '-fno-inline' to manipulate the pass
  pipeline which forced the pass pipeline to be much more
  parameterizable than it really needs to be. Instead we can *just* use
  the optimization level to select a pipeline and control the rest via
  attributes.

Sadly, this causes a bunch of churn in tests because we don't run the
optimizer in the tests and check the contents of attribute sets. It
would be awesome if attribute sets were a bit more FileCheck friendly,
but oh well.

I think this is a significant improvement and should remove the semantic
need to change what inliner pass we run in order to comply with the
requested inlining semantics by relying completely on attributes. It
also cleans up tho optnone and related handling a bit.

One unfortunate aspect of this is that for generating alwaysinline
routines like those in OpenMP we end up removing noinline and then
adding alwaysinline. I tried a bunch of other approaches, but because we
recompute function attributes from scratch and don't have a declaration
here I couldn't find anything substantially cleaner than this.

Differential Revision: https://reviews.llvm.org/D28053

llvm-svn: 290398
2016-12-23 01:24:49 +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
Pekka Jaaskelainen 2a1cc587bf [OpenCL] always use SPIR address spaces for kernel_arg_addr_space MD
It doesn't make sense to use the target's address space ids in this context as
this is metadata that should be referring to the "logical" OpenCL address spaces.
For flat AS machines like all "CPUs" in general, the logical AS info gets lost as
there's only one address space (0).

This commit changes the logic such that we always use the SPIR address space
ids for the argument metadata. It thus allows implementing the clGetKernelArgInfo()
and the other detection needs.

https://reviews.llvm.org/D26157

llvm-svn: 286819
2016-11-14 13:08:30 +00:00
Anna Zaks bcd35a8ec1 [tsan][clang] Introduce a function attribute to disable TSan checking at run time
This introduces a function annotation that disables TSan checking for the
function at run time. The benefit over attribute((no_sanitize("thread")))
is that the accesses within the callees will also be suppressed.

The motivation for this attribute is a guarantee given by the objective C
language that the calls to the reference count decrement and object
deallocation will be synchronized. To model this properly, we would need to
intercept all ref count decrement calls (which are very common in ObjC due
to use of ARC) and also every single message send. Instead, we propose to
just ignore all accesses made from within dealloc at run time. The main
downside is that this still does not introduce any synchronization, which
means we might still report false positives if the code that relies on this
synchronization is not executed from within dealloc. However, we have not
seen this in practice so far and think these cases will be very rare.

(This problem is similar in nature to https://reviews.llvm.org/D21609;
unfortunately, the same solution does not apply here.)

Differential Revision: https://reviews.llvm.org/D25857

llvm-svn: 286672
2016-11-11 23:22:44 +00:00
Amara Emerson 652795db16 Add the loop end location to the loop metadata. This additional information
can be used to improve the locations when generating remarks for loops.

Depends on the companion LLVM change r286227.

Patch by Florian Hahn.

Differential Revision: https://reviews.llvm.org/D25764

llvm-svn: 286456
2016-11-10 14:44:30 +00:00
Vitaly Buka 64c80b4e39 [CodeGen] Don't emit lifetime intrinsics for some local variables
Summary:
Current generation of lifetime intrinsics does not handle cases like:

```
  {
    char x;
  l1:
    bar(&x, 1);
  }
  goto l1;

```
We will get code like this:

```
  %x = alloca i8, align 1
  call void @llvm.lifetime.start(i64 1, i8* nonnull %x)
  br label %l1
l1:
  %call = call i32 @bar(i8* nonnull %x, i32 1)
  call void @llvm.lifetime.end(i64 1, i8* nonnull %x)
  br label %l1
```

So the second time bar was called for x which is marked as dead.
Lifetime markers here are misleading so it's better to remove them at all.
This type of bypasses are rare, e.g. code detects just 8 functions building
clang (2329 targets).

PR28267

Reviewers: eugenis

Subscribers: beanz, mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D24693

llvm-svn: 285176
2016-10-26 05:42:30 +00:00
Vitaly Buka 1c94332e7a [CodeGen] Move shouldEmitLifetimeMarkers into more convenient place
Summary: D24693 will need access to it from other places

Reviewers: eugenis

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D24695

llvm-svn: 285158
2016-10-26 01:59:57 +00:00
Richard Smith d8e3ac3185 Fix a couple of wrong-code bugs in switch-on-constant optimization:
* recurse through intermediate LabelStmts and AttributedStmts when checking
   whether a statement inside a switch declares a variable
 * if the end of a compound statement is reachable from the chosen case label,
   and the compound statement contains a variable declaration, it's not valid
   to just emit the contents of the compound statement -- we must emit the
   statement itself or we lose the scope (and thus end lifetimes at the wrong
   point)

llvm-svn: 281797
2016-09-16 23:30:39 +00:00
Manman Ren e6be26c8d4 ObjectiveC generics: Add ObjCTypeParamType in the type system.
We also need to add ObjCTypeParamTypeLoc. ObjCTypeParamType supports the
representation of "T <protocol>" where T is a type parameter. Before this,
we use TypedefType to represent the type parameter for ObjC.

ObjCTypeParamType has "ObjCTypeParamDecl *OTPDecl" and it extends from
ObjCProtocolQualifiers. It is a non-canonical type and is canonicalized
to the underlying type with the protocol qualifiers.

rdar://24619481
rdar://25060179

Differential Revision: http://reviews.llvm.org/D23079

llvm-svn: 281355
2016-09-13 17:25:08 +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
Alexey Bader 3e0b817b91 [OpenCL] Remove access qualifiers on images in arg info metadata.
Summary:
Remove access qualifiers on images in arg info metadata:
 * kernel_arg_type
 * kernel_arg_base_type

Image access qualifiers are inseparable from type in clang implementation,
but OpenCL spec provides a special query to get access qualifier
via clGetKernelArgInfo with CL_KERNEL_ARG_ACCESS_QUALIFIER.

Besides that OpenCL conformance test_api get_kernel_arg_info expects
image types without access qualifier.

Patch by Evgeniy Tyurin.

Reviewers: bader, yaxunl, Anastasia

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D23915

llvm-svn: 280699
2016-09-06 10:10:28 +00:00
Honggyu Kim 2b0e424b2f [Frontend] Fix mcount inlining bug
Since some profiling tools, such as gprof, ftrace, and uftrace, use
-pg option to generate a mcount function call at the entry of each
function. Function invocation can be detected by this hook function.

But mcount insertion is done before function inlining phase in clang,
sometime a function that already has a mcount call can be inlined in the
middle of another function.

This patch adds an attribute "counting-function" to each function
rather than emitting the mcount call directly in frontend so that this
attribute can be processed in backend. Then the mcount calls can be
properly inserted in backend after all the other optimizations are
completed.

Link: https://llvm.org/bugs/show_bug.cgi?id=28660

Reviewers: hans, rjmccall, hfinkel, rengolin, compnerd

Subscribers: shenhan, cfe-commits

Differential Revision: https://reviews.llvm.org/D22666

llvm-svn: 280355
2016-09-01 11:29:21 +00:00
Honggyu Kim 2bbdeacf31 Remove whitespace to test commit access
llvm-svn: 280337
2016-09-01 06:14:45 +00:00
Aaron Ballman 7d2aecbc76 Add XRay flags to Clang. We implement two flags to control the XRay behaviour:
-fxray-instrument: enables XRay annotation of IR
-fxray-instruction-threshold: configures the threshold for function size (looking at IR instructions), and allow LLVM to decide whether to add the nop sleds later on in the process.

Also implements the related xray_always_instrument and xray_never_instrument function attributes.

Patch by Dean Michael Berris.

llvm-svn: 275330
2016-07-13 22:32:15 +00:00
Alexey Bader 10e9e59898 [OpenCL] Fix code generation of kernel pipe parameters.
Improved test with user define structure pipe type case.

Reviewers: Anastasia, pxli168
Subscribers: yaxunl, cfe-commits

Differential revision: http://reviews.llvm.org/D21744

llvm-svn: 275259
2016-07-13 10:28:13 +00:00
Richard Smith 5179eb7821 P0136R1, DR1573, DR1645, DR1715, DR1736, DR1903, DR1941, DR1959, DR1991:
Replace inheriting constructors implementation with new approach, voted into
C++ last year as a DR against C++11.

Instead of synthesizing a set of derived class constructors for each inherited
base class constructor, we make the constructors of the base class visible to
constructor lookup in the derived class, using the normal rules for
using-declarations.

For constructors, UsingShadowDecl now has a ConstructorUsingShadowDecl derived
class that tracks the requisite additional information. We create shadow
constructors (not found by name lookup) in the derived class to model the
actual initialization, and have a new expression node,
CXXInheritedCtorInitExpr, to model the initialization of a base class from such
a constructor. (This initialization is special because it performs real perfect
forwarding of arguments.)

In cases where argument forwarding is not possible (for inalloca calls,
variadic calls, and calls with callee parameter cleanup), the shadow inheriting
constructor is not emitted and instead we directly emit the initialization code
into the caller of the inherited constructor.

Note that this new model is not perfectly compatible with the old model in some
corner cases. In particular:
 * if B inherits a private constructor from A, and C uses that constructor to
   construct a B, then we previously required that A befriends B and B
   befriends C, but the new rules require A to befriend C directly, and
 * if a derived class has its own constructors (and so its implicit default
   constructor is suppressed), it may still inherit a default constructor from
   a base class

llvm-svn: 274049
2016-06-28 19:03:57 +00:00
David Majnemer 59f7792136 Use more ArrayRefs
No functional change is intended, just a small refactoring.

llvm-svn: 273647
2016-06-24 04:05:48 +00:00
Richard Smith b130fe7d31 Implement p0292r2 (constexpr if), a likely C++1z feature.
llvm-svn: 273602
2016-06-23 19:16:49 +00:00
Hans Wennborg 44d061a471 Add support for /Ob1 and -finline-hint-functions flags
Add support for /Ob1 (and equivalent -finline-hint-functions), which enable
inlining only for functions marked inline, either explicitly (via inline
keyword, for example), or implicitly (function definition in class body,
for example).

This works by enabling inlining pass, and adding noinline attribute to
every function not marked inline.

Patch by Rudy Pons <rudy.pons@ilod.org>!

Differential Revision: http://reviews.llvm.org/D20647

llvm-svn: 273440
2016-06-22 16:56:16 +00:00
Yaxun Liu ba28cba882 [OpenCL] Use function metadata to represent kernel attributes
This patch uses function metadata to represent reqd_work_group_size, work_group_size_hint and vector_type_hint kernel attributes and kernel argument info.

Differential Revision: http://reviews.llvm.org/D20979

llvm-svn: 273425
2016-06-22 14:56:35 +00:00
Reid Kleckner f00f803294 [DebugInfo] Add calling conventions to DISubroutineType
Summary:
This should have been a very simple change, but it was greatly
complicated by the construction of new Decls during IR generation.

In particular, we reconstruct the AST function type in order to get the
implicit 'this' parameter into C++ method types.

We also have to worry about FunctionDecls whose types are not
FunctionTypes because CGBlocks.cpp constructs some dummy FunctionDecls
with 'void' type.

Depends on D21114

Reviewers: aprantl, dblaikie

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D21141

llvm-svn: 272198
2016-06-08 20:41:54 +00:00
Alexey Bataev c7a82b41a7 [OPENMP 4.0] Codegen for 'declare simd' directive.
OpenMP 4.0 adds support for elemental functions using declarative
directive '#pragma omp declare simd'. Patch adds mangling for simd
functions in accordance with
https://sourceware.org/glibc/wiki/libmvec?action=AttachFile&do=view&target=VectorABI.txt

llvm-svn: 268721
2016-05-06 09:40:08 +00:00
Adrian Prantl 06f445d65b Debug info: Apply an artificial debug location to __cyg_profile_func.* calls.
The LLVM Verifier expects all inlinable calls in debuggable functions to
have a location.

rdar://problem/25818489

llvm-svn: 267904
2016-04-28 17:21:56 +00:00
Sanjay Patel 3fd323fa36 reduce indentation; NFCI
llvm-svn: 266787
2016-04-19 18:06:33 +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
Sanjoy Das f60a0d7452 Adapt to LLVM API change
Replace mayBeOverridden with isInterposable

llvm-svn: 265767
2016-04-08 01:31:02 +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
Nirav Dave d2f44d8de0 Add -fno-jump-tables and-fjump-tables flags
Add no-jump-tables flag to disable use of jump tables when lowering
switch statements

Reviewers: echristo, hans

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18407

llvm-svn: 265425
2016-04-05 17:50:43 +00:00
Faisal Vali dc6b596ebb [Cxx1z] Implement Lambda Capture of *this by Value as [=,*this] (P0018R3)
Implement lambda capture of *this by copy.
For e.g.:
struct A {

  int d = 10;
  auto foo() { return [*this] (auto a) mutable { d+=a; return d; }; }

};

auto L = A{}.foo(); // A{}'s lifetime is gone.

// Below is still ok, because *this was captured by value.
assert(L(10) == 20);
assert(L(100) == 120);

If the capture was implicit, or [this] (i.e. *this was captured by reference), this code would be otherwise undefined.

Implementation Strategy:
  - amend the parser to accept *this in the lambda introducer
  - add a new king of capture LCK_StarThis
  - teach Sema::CheckCXXThisCapture to handle by copy captures of the
    enclosing object (i.e. *this)
  - when CheckCXXThisCapture does capture by copy, the corresponding 
    initializer expression for the closure's data member 
    direct-initializes it thus making a copy of '*this'.
  - in codegen, when assigning to CXXThisValue, if *this was captured by 
    copy, make sure it points to the corresponding field member, and
    not, unlike when captured by reference, what the field member points
    to.
  - mark feature as implemented in svn

Much gratitude to Richard Smith for his carefully illuminating reviews!   

llvm-svn: 263921
2016-03-21 09:25:37 +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
David Majnemer 25eb165f18 [MSVC Compat] Correctly handle finallys nested within finallys
We'd lose track of the parent CodeGenFunction, leading us to get
confused with regard to which function a nested finally belonged to.

Differential Revision: http://reviews.llvm.org/D17752

llvm-svn: 262379
2016-03-01 19:42:53 +00:00
Xiuli Pan 11e13f60ea [OpenCL] Refine OpenCLImageAccessAttr to OpenCLAccessAttr
Summary:
OpenCL access qualifiers are now not only used for image types, refine it to avoid misleading,

Add semacheck for OpenCL access qualifier as well as test caees.

Reviewers: pekka.jaaskelainen, Anastasia, aaron.ballman

Subscribers: aaron.ballman, cfe-commits

Differential Revision: http://reviews.llvm.org/D16040

llvm-svn: 261961
2016-02-26 03:13:03 +00:00
Rong Xu 9837ef56b4 [PGO] cc1 option name change for profile instrumentation
This patch changes cc1 option -fprofile-instr-generate to an enum option
-fprofile-instrument={clang|none}. It also changes cc1 options
-fprofile-instr-generate= to -fprofile-instrument-path=.
The driver level option -fprofile-instr-generate and -fprofile-instr-generate=
remain intact. This change will pave the way to integrate new PGO
instrumentation in IR level.

Review: http://reviews.llvm.org/D16730
llvm-svn: 259811
2016-02-04 18:39:09 +00:00
Benjamin Kramer 8c30592e18 Move DebugInfoKind into its own header to cut the cyclic dependency edge from Driver to Frontend.
llvm-svn: 259489
2016-02-02 11:06:51 +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
Sanjay Patel d61f3c71c3 function names start with a lower case letter ; NFC
llvm-svn: 257497
2016-01-12 18:03:41 +00:00
Xiuli Pan 9c14e28211 [OpenCL] Pipe type support
Summary:
Support for OpenCL 2.0 pipe type.
This is a bug-fix version for bader's patch reviews.llvm.org/D14441


Reviewers: pekka.jaaskelainen, Anastasia

Subscribers: bader, Anastasia, cfe-commits

Differential Revision: http://reviews.llvm.org/D15603

llvm-svn: 257254
2016-01-09 12:53:17 +00:00
Serge Pavlov 3a5614599a [PGO] Instrument only base constructors and destructors.
Constructors and destructors may be represented by several functions
in IR. Only base structors correspond to source code, others are
small pieces of code and eventually call the base variant. In this
case instrumentation of non-base structors has little sense, this
fix remove it. Now profile data of a declaration corresponds to
exactly one function in IR, it agrees with the current logic of the
profile data loading.

This change fixes PR24996.

Differential Revision: http://reviews.llvm.org/D15158

llvm-svn: 254876
2015-12-06 14:32:39 +00:00
George Burgess IV 3e3bb95b69 Add the `pass_object_size` attribute to clang.
`pass_object_size` is our way of enabling `__builtin_object_size` to
produce high quality results without requiring inlining to happen
everywhere.

A link to the design doc for this attribute is available at the
Differential review link below.

Differential Revision: http://reviews.llvm.org/D13263

llvm-svn: 254554
2015-12-02 21:58:08 +00:00
Eric Christopher b7bbc53314 When producing error messages for always_inline functions with the
target attribute, don't include "negative" subtarget features in the
list of required features. Builtins are positive by default so don't
need this change, but we pull the default list of features from the
command line and so need to make sure that we only include features
that are turned on for code generation in our error.

llvm-svn: 253242
2015-11-16 18:29:59 +00:00
Eric Christopher ce83677666 Add support for the always_inline + target feature diagnostic to print
out the first missing target feature that's required and reword
the diagnostic accordingly.

llvm-svn: 253121
2015-11-14 02:38:37 +00:00
James Molloy c16a60b63e [C++] Add the "norecurse" attribute to main() if in C++ mode
The C++ spec (3.6.1.3) says "The function `main` shall not be used within a program". This implies that it cannot recurse, so add the norecurse attribute to help the midend out a bit.

llvm-svn: 252902
2015-11-12 15:36:04 +00:00
David Blaikie 5df25338a0 Refactor out some common code from r252834
llvm-svn: 252840
2015-11-12 01:09:58 +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
Eric Christopher fbfd97ed5c Move checkTargetFeatures to CodeGenFunction.cpp to make it
more obvious that it's generic.

llvm-svn: 252833
2015-11-12 00:44:07 +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
Angel Garcia Gomez 637d1e6694 Roll-back r250822.
Summary: It breaks the build for the ASTMatchers

Subscribers: klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D13893

llvm-svn: 250827
2015-10-20 13:23:58 +00:00
Angel Garcia Gomez b5250d3448 Apply modernize-use-default to clang.
Summary: Replace empty bodies of default constructors and destructors with '= default'.

Reviewers: bkramer, klimek

Subscribers: klimek, alexfh, cfe-commits

Differential Revision: http://reviews.llvm.org/D13890

llvm-svn: 250822
2015-10-20 12:52:55 +00:00
Charles Davis c7d5c94f78 Support __builtin_ms_va_list.
Summary:
This change adds support for `__builtin_ms_va_list`, a GCC extension for
variadic `ms_abi` functions. The existing `__builtin_va_list` support is
inadequate for this because `va_list` is defined differently in the Win64
ABI vs. the System V/AMD64 ABI.

Depends on D1622.

Reviewers: rsmith, rnk, rjmccall

CC: cfe-commits

Differential Revision: http://reviews.llvm.org/D1623

llvm-svn: 247941
2015-09-17 20:55:33 +00:00
David Majnemer 9df56372e8 [MS ABI] Make member pointers return true for isIncompleteType
The type of a member pointer is incomplete if it has no inheritance
model.  This lets us reuse more general logic already embedded in clang.

llvm-svn: 247346
2015-09-10 21:52:00 +00:00
John McCall 7f416cc426 Compute and preserve alignment more faithfully in IR-generation.
Introduce an Address type to bundle a pointer value with an
alignment.  Introduce APIs on CGBuilderTy to work with Address
values.  Change core APIs on CGF/CGM to traffic in Address where
appropriate.  Require alignments to be non-zero.  Update a ton
of code to compute and propagate alignment information.

As part of this, I've promoted CGBuiltin's EmitPointerWithAlignment
helper function to CGF and made use of it in a number of places in
the expression emitter.

The end result is that we should now be significantly more correct
when performing operations on objects that are locally known to
be under-aligned.  Since alignment is not reliably tracked in the
type system, there are inherent limits to this, but at least we
are no longer confused by standard operations like derived-to-base
conversions and array-to-pointer decay.  I've also fixed a large
number of bugs where we were applying the complete-object alignment
to a pointer instead of the non-virtual alignment, although most of
these were hidden by the very conservative approach we took with
member alignment.

Also, because IRGen now reliably asserts on zero alignments, we
should no longer be subject to an absurd but frustrating recurring
bug where an incomplete type would report a zero alignment and then
we'd naively do a alignmentAtOffset on it and emit code using an
alignment equal to the largest power-of-two factor of the offset.

We should also now be emitting much more aggressive alignment
attributes in the presence of over-alignment.  In particular,
field access now uses alignmentAtOffset instead of min.

Several times in this patch, I had to change the existing
code-generation pattern in order to more effectively use
the Address APIs.  For the most part, this seems to be a strict
improvement, like doing pointer arithmetic with GEPs instead of
ptrtoint.  That said, I've tried very hard to not change semantics,
but it is likely that I've failed in a few places, for which I
apologize.

ABIArgInfo now always carries the assumed alignment of indirect and
indirect byval arguments.  In order to cut down on what was already
a dauntingly large patch, I changed the code to never set align
attributes in the IR on non-byval indirect arguments.  That is,
we still generate code which assumes that indirect arguments have
the given alignment, but we don't express this information to the
backend except where it's semantically required (i.e. on byvals).
This is likely a minor regression for those targets that did provide
this information, but it'll be trivial to add it back in a later
patch.

I partially punted on applying this work to CGBuiltin.  Please
do not add more uses of the CreateDefaultAligned{Load,Store}
APIs; they will be going away eventually.

llvm-svn: 246985
2015-09-08 08:05:57 +00:00
Sanjay Patel a24296b459 add __builtin_unpredictable and convert to metadata
This patch depends on r246688 (D12341).

The goal is to make LLVM generate different code for these functions for a target that
has cheap branches (see PR23827 for more details):

int foo();

int normal(int x, int y, int z) {
   if (x != 0 && y != 0) return foo();
   return 1;
}

int crazy(int x, int y) {
   if (__builtin_unpredictable(x != 0 && y != 0)) return foo();
   return 1;
}

Differential Revision: http://reviews.llvm.org/D12458

llvm-svn: 246699
2015-09-02 20:01:30 +00:00
David Majnemer dbf1045ad7 [MS ABI] Hook clang up to the new EH instructions
The new EH instructions make it possible for LLVM to generate .xdata
tables that the MSVC personality routines will be happy about.  Because
this is experimental, hide it behind a -cc1 flag (-fnew-ms-eh).

Differential Revision: http://reviews.llvm.org/D11405

llvm-svn: 243767
2015-07-31 17:58:45 +00:00
Reid Kleckner 98cb8ba64c Update clang for intrinsic rename of framerecover to localrecover
llvm-svn: 241634
2015-07-07 22:26:07 +00:00
Reid Kleckner 9fe7f2396b Revert "Revert 241171, 241187, 241199 (32-bit SEH)."
This reverts commit r241244, but restricts SEH support to Win64.

This way, Chromium builds will still fall back on TUs with SEH, and
Clang developers can work on this incrementally upstream while patching
this small predicate locally. It'll also make it easier to review small
fixes.

llvm-svn: 241533
2015-07-07 00:36:30 +00:00
Akira Hatanaka 85365cd72a Attach attribute "trap-func-name" to call sites of llvm.trap and llvm.debugtrap.
This is needed to use clang's command line option "-ftrap-function" for LTO and
enable changing the trap function name on a per-call-site basis.

rdar://problem/21225723

Differential Revision: http://reviews.llvm.org/D10831

llvm-svn: 241306
2015-07-02 22:15:41 +00:00
Benjamin Kramer 642f173ae9 Switch users of the 'for (StmtRange range = stmt->children(); range; ++range)‘ pattern to range for loops.
The pattern was born out of the lack of range-based for loops in C++98
and is somewhat obscure. No functionality change intended.

llvm-svn: 241300
2015-07-02 21:03:14 +00:00
Nico Weber e4f974c6fb Revert 241171, 241187, 241199 (32-bit SEH).
It still doesn't produce quite the right code, test binaries built with this
enabled fail some tests.

llvm-svn: 241244
2015-07-02 06:10:53 +00:00
Reid Kleckner d0d9a1f63f [SEH] Add 32-bit lowering for SEH __try
This re-lands r236052 and adds support for __exception_code().

In 32-bit SEH, the exception code is not available in eax. It is only
available in the filter function, and now we arrange to load it and
store it into an escaped variable in the parent frame.

As a consequence, we have to disable the "catch i8* null" optimization
on 32-bit and always generate a filter function. We can re-enable the
optimization if we detect an __except block that doesn't use the
exception code, but this probably isn't worth optimizing.

Reviewers: majnemer

Differential Revision: http://reviews.llvm.org/D10852

llvm-svn: 241171
2015-07-01 17:10:10 +00:00
Alexander Potapenko b9b73ef906 [ASan] Initial support for Kernel AddressSanitizer
This patch adds initial support for the -fsanitize=kernel-address flag to Clang.
Right now it's quite restricted: only out-of-line instrumentation is supported, globals are not instrumented, some GCC kasan flags are not supported.
Using this patch I am able to build and boot the KASan tree with LLVMLinux patches from github.com/ramosian-glider/kasan/tree/kasan_llvmlinux.
To disable KASan instrumentation for a certain function attribute((no_sanitize("kernel-address"))) can be used.

llvm-svn: 240131
2015-06-19 12:19:07 +00:00
Peter Collingbourne c4122c17b4 Protection against stack-based memory corruption errors using SafeStack: Clang command line option and function attribute
This patch adds the -fsanitize=safe-stack command line argument for clang,
which enables the Safe Stack protection (see http://reviews.llvm.org/D6094
for the detailed description of the Safe Stack).

This patch is our implementation of the safe stack on top of Clang. The
patches make the following changes:

- Add -fsanitize=safe-stack and -fno-sanitize=safe-stack options to clang
  to control safe stack usage (the safe stack is disabled by default).

- Add __attribute__((no_sanitize("safe-stack"))) attribute to clang that can be
  used to disable the safe stack for individual functions even when enabled
  globally.

Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.

Differential Revision: http://reviews.llvm.org/D6095

llvm-svn: 239762
2015-06-15 21:08:13 +00:00
Reid Kleckner 0b9bbbfc13 Revert "Re-land r236052, "[SEH] Add 32-bit lowering code for __try""
This reverts commit r239415. This was committed accidentally, LLVM isn't
ready for this.

llvm-svn: 239417
2015-06-09 17:49:42 +00:00
Reid Kleckner 65870442b3 Re-land r236052, "[SEH] Add 32-bit lowering code for __try"
This reverts r236167.

LLVM should be ready for this now.

llvm-svn: 239415
2015-06-09 17:47:50 +00:00
David Blaikie 43f9bb7371 API update for streamlining of IRBuilder::CreateCall to just use ArrayRef/initializer_list+braced init
llvm-svn: 237625
2015-05-18 22:14:03 +00:00
Peter Collingbourne 915df9968b Implement no_sanitize attribute.
Differential Revision: http://reviews.llvm.org/D9631

llvm-svn: 237463
2015-05-15 18:33:32 +00:00
Artem Belevich 52cc487ba8 [cuda] Include GPU binary into host object file and generate init/deinit code.
- added -fcuda-include-gpubinary option to incorporate results of
  device-side compilation into host-side one.
- generate code to register GPU binaries and associated kernels
  with CUDA runtime and clean-up on exit.
- added test case for init/deinit code generation.

Differential Revision: http://reviews.llvm.org/D9507

llvm-svn: 236765
2015-05-07 19:34:16 +00:00
Justin Bogner 65512647cc InstrProf: Cede ownership of createProfileWeights to CGF
The fact that PGO has a say in how these branch weights are determined
isn't interesting to most of CodeGen, so it makes more sense for this
API to be accessible via CodeGenFunction rather than CodeGenPGO.

llvm-svn: 236380
2015-05-02 05:00:55 +00:00
Reid Kleckner cb7a0a0562 Revert most of r236271, leaving only the datalayout change in lib/Basic/Targets.cpp
llvm-svn: 236274
2015-04-30 22:29:25 +00:00
Reid Kleckner af67602e14 Use 4 byte preferred aggregate alignment in datalayout on x86 Win32
llvm-svn: 236271
2015-04-30 22:13:05 +00:00
Reid Kleckner be9843ce54 Revert r236128, LLVM isn't falling back in the right way
llvm-svn: 236167
2015-04-29 21:55:21 +00:00
Reid Kleckner 0bb12a8981 Re-land r236052, the linker errors were fixed by LLVM r236123
Basic __finally blocks don't cause linker errors anymore (although they
are miscompiled).

llvm-svn: 236128
2015-04-29 17:17:17 +00:00
Nico Weber ea721b64df Revert r236052, it caused linker errors when building 32-bit applications.
llvm-svn: 236082
2015-04-29 03:08:32 +00:00
Reid Kleckner ddd40964f0 [SEH] Add 32-bit lowering code for __try
This is just the clang-side of 32-bit SEH. LLVM still needs work, and it
will determinstically fail to compile until it's feature complete.

On x86, all outlined handlers have no parameters, but they do implicitly
take the EBP value passed in and use it to address locals of the parent
frame. We model this with llvm.frameaddress(1).

This works (mostly), but __finally block inlining can break it. For now,
we apply the 'noinline' attribute. If we really want to inline __finally
blocks on 32-bit x86, we should teach the inliner how to untangle
frameescape and framerecover.

Promote the error diagnostic from codegen to sema. It now rejects SEH on
non-Windows platforms. LLVM doesn't implement SEH on non-x86 Windows
platforms, but there's nothing preventing it.

llvm-svn: 236052
2015-04-28 22:19:32 +00:00
Justin Bogner 66242d6c5e InstrProf: Stop using RegionCounter outside of CodeGenPGO (NFC)
The RegionCounter type does a lot of legwork, but most of it is only
meaningful within the implementation of CodeGenPGO. The uses elsewhere
in CodeGen generally just want to increment or read counters, so do
that directly.

llvm-svn: 235664
2015-04-23 23:06:47 +00:00
David Majnemer dc012fa266 Revert "Revert r234581, it might have caused a few miscompiles in Chromium."
This reverts commit r234700.  It turns out that the lifetime markers
were not the cause of Chromium failing but a bug which was uncovered by
optimizations exposed by the markers.

llvm-svn: 235553
2015-04-22 21:38:15 +00:00
Reid Kleckner ebaf28d13d Reland r234613 (and follow-ups 234614, 234616, 234618)
The frameescape intrinsic cannot be inlined, so I fixed the inliner in
r234937. This should address PR23216.

llvm-svn: 234942
2015-04-14 20:59:00 +00:00
Nico Weber ad108337cf Revert r234613 (and follow-ups 234614, 234616, 234618), it caused PR23216.
llvm-svn: 234789
2015-04-13 20:04:22 +00:00
Nico Weber f2a39a7b4e Revert r234786, it contained a bunch of stuff I did not mean to commit.
llvm-svn: 234787
2015-04-13 20:03:03 +00:00
Nico Weber b31abb05fb Revert r234613 (and follow-ups 234614, 234616, 234618), it caused PR23216.
llvm-svn: 234786
2015-04-13 20:01:20 +00:00
Nico Weber 1c565c31b1 Revert r234581, it might have caused a few miscompiles in Chromium.
If the revert helps, I'll get a repro this Monday.  Else I'll put the change
back in.

llvm-svn: 234700
2015-04-11 23:51:38 +00:00
Reid Kleckner 11859afd5f [SEH] Re-land r234532, but use internal linkage for all SEH helpers
Even though these symbols are in a comdat group, the Microsoft linker
really wants them to have internal linkage.

I'm planning to tweak the mangling in a follow-up change. This is a
straight revert with a 1-line fix.

llvm-svn: 234613
2015-04-10 17:34:52 +00:00
Arnaud A. de Grandmaison 047a686d53 Remove threshold for inserting lifetime markers for named temporaries
Now that TailRecursionElimination has been fixed with r222354, the
threshold on size for lifetime marker insertion can be removed. This
only affects named temporary though, as the patch for unnamed temporaries
is still in progress.

My previous commit (r222993) was not handling debuginfo correctly, but
this could only be seen with some asan tests. Basically, lifetime markers
are just instrumentation for the compiler's usage and should not affect
debug information; however, the cleanup infrastructure was assuming it
contained only destructors, i.e. actual code to be executed, and was
setting the breakpoint for the end of the function to the closing '}', and
not the return statement, in order to show some destructors have been
called when leaving the function. This is wrong when the cleanups are only
lifetime markers, and this is now fixed.

llvm-svn: 234581
2015-04-10 10:13:52 +00:00
Nico Weber bd51a6a99f Revert r234532 for a bit, it very likely caused http://crbug.com/475768
llvm-svn: 234563
2015-04-10 04:33:03 +00:00
Reid Kleckner 0dbecf2b78 [SEH] Outline finally blocks using the new variable capture support
WinEHPrepare was going to have to pattern match the control flow merge
and split that the old lowering used, and that wasn't really feasible.

Now we can teach WinEHPrepare to pattern match this, which is much
simpler:
  %fp = call i8* @llvm.frameaddress(i32 0)
  call void @func(iN [01], i8* %fp)

This prototype happens to match the prototype used by the Win64 SEH
personality function, so this is really simple.

llvm-svn: 234532
2015-04-09 20:37:24 +00:00
Sanjay Patel 359b105745 Process the -freciprocal-math optimization flag (PR20912)
The driver currently accepts but ignores the -freciprocal-math flag.
This patch passes the flag through and enables 'arcp' fast-math-flag
generation in IR.

Note that this change does not actually enable the optimization for
any target. The reassociation optimization that this flag specifies
was implemented by http://reviews.llvm.org/D6334 :
http://llvm.org/viewvc/llvm-project?view=revision&revision=222510

Because the optimization is done in the backend rather than IR,
the backend must be modified to understand instruction-level
fast-math-flags or a new function-level attribute must be created.

Also note that -freciprocal-math is independent of any target-specific
usage of reciprocal estimate hardware instructions. That requires
its own flag ('-mrecip').

https://llvm.org/bugs/show_bug.cgi?id=20912

llvm-svn: 234493
2015-04-09 15:03:23 +00:00
Reid Kleckner 31a1bb0c14 Reland "[SEH] Implement filter capturing in CodeGen"
The test should be fixed. It was failing in NDEBUG builds due to a
missing '*' character in a regex. In asserts builds, the pattern matched
a single digit value, which became a double digit value in NDEBUG
builds. Go figure.

This reverts commit r234261.

llvm-svn: 234447
2015-04-08 22:23:48 +00:00
Daniel Jasper 303c3ac925 Revert "[SEH] Implement filter capturing in CodeGen"
Test fails:
http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto_check/3182/

llvm-svn: 234306
2015-04-07 10:07:47 +00:00
Reid Kleckner 0ada50f17f [SEH] Implement filter capturing in CodeGen
While capturing filters aren't very common, we'd like to outline
__finally blocks in the frontend to simplify -O0 EH preparation and
reduce code size. Finally blocks are usually have captures, and this is
the first step towards that.

Currently we don't support capturing 'this' or VLAs.

Reviewers: majnemer

Differential Revision: http://reviews.llvm.org/D8825

llvm-svn: 234261
2015-04-06 23:51:44 +00:00
David Blaikie 1ed728c499 [opaque pointer type] More GEP API migrations
Looks like the VTable code in particular will need some work to pass
around the pointee type explicitly.

llvm-svn: 234128
2015-04-05 22:45:47 +00:00
David Blaikie fb901c7abf [opaque pointer type] more GEP API migrations
llvm-svn: 234097
2015-04-04 15:12:29 +00:00
Reid Kleckner 7ffc3fbb2f C++14: Disable sized deallocation by default due to ABI breakage
There are no widely deployed standard libraries providing sized
deallocation functions, so we have to punt and ask the user if they want
us to use sized deallocation. In the future, when such libraries are
deployed, we can teach the driver to detect them and enable this
feature.

N3536 claimed that a weak thunk from sized to unsized deallocation could
be emitted to avoid breaking backwards compatibility with standard
libraries not providing sized deallocation. However, this approach and
other variations don't work in practice.

With the weak function approach, the thunk has to have default
visibility in order to ensure that it is overridden by other DSOs
providing sized deallocation. Weak, default visibility symbols are
particularly expensive on MachO, so John McCall was considering
disabling this feature by default on Darwin. It also changes behavior
ELF linking behavior, causing certain otherwise unreferenced object
files from an archive to be pulled into the link.

Our second approach was to use an extern_weak function declaration and
do an inline conditional branch at the deletion call site. This doesn't
work because extern_weak only works on MachO if you have some archive
providing the default value of the extern_weak symbol. Arranging to
provide such an archive has the same challenges as providing the symbol
in the standard library. Not to mention that extern_weak doesn't really
work on COFF.

Reviewers: rsmith, rjmccall

Differential Revision: http://reviews.llvm.org/D8467

llvm-svn: 232788
2015-03-20 00:31:07 +00:00
Artem Belevich f3d3db65de Remove .CUDAIsDevice flags from CodeGenOpts as it's already
available in LangOpts.

Differential Revision: http://reviews.llvm.org/D8385

llvm-svn: 232749
2015-03-19 18:58:18 +00:00
Alexey Bataev 3eff5f46d7 [OPENMP] Rename methods of OpenMPRuntime class. NFC.
llvm-svn: 230470
2015-02-25 08:32:46 +00:00
Reid Kleckner 4343922dde Avoid using a COMDAT for sized delete on MachO
llvm-svn: 229915
2015-02-19 21:13:45 +00:00
Reid Kleckner 66abf2f92f Put the implicit weak sized deallocation funciton in C++14 in a comdat
Fixes PR22635.

llvm-svn: 229913
2015-02-19 21:01:34 +00:00
Larisse Voufo e990a3f60c Rename flags and options to match current naming: from -fdef-sized-delete to -fdefine-sized-deallocation, and from DefaultSizedDelete to DefineSizedDeallocation.
llvm-svn: 229597
2015-02-18 01:04:10 +00:00
Larisse Voufo 5526f4f094 Revise the implementation logic of sized deallocation: Do not automatically generate weak definitions of the sized operator delete (in terms of unsized operator delete). Instead, provide the funcitonality via a new compiler flag, -fdef-sized-delete.
The current implementation causes link-time ODR violations when the delete symbols are exported into the dynamic table.

llvm-svn: 229241
2015-02-14 05:42:57 +00:00
Reid Kleckner 11c033e8aa SEH: Use the SEHTryEpilogueStack instead of a separate bool
We don't need a bool to track this now that we have a stack for it.

llvm-svn: 228982
2015-02-12 23:40:45 +00:00
Reid Kleckner a593000f01 Add the 'noinline' attribute to call sites within __try bodies
LLVM doesn't support non-call exceptions, so inlining makes it harder to
catch such asynchronous exceptions.

llvm-svn: 228876
2015-02-11 21:40:48 +00:00
Reid Kleckner aca01db706 Implement IRGen for SEH __finally and AbnormalTermination
Previously we would simply double-emit the body of the __finally block,
but that doesn't work when it contains any kind of Decl, which we can't
double emit.

This fixes that by emitting the block once and branching into a shared
code region and then branching back out.

llvm-svn: 228222
2015-02-04 22:37:07 +00:00
David Blaikie 4d52443c0e DebugInfo: Attribute cleanup code to the end of the scope, not the end of the function.
Now if you break on a dtor and go 'up' in your debugger (or you get an
asan failure in a dtor) during an exception unwind, you'll have more
context. Instead of all dtors appearing to be called from the '}' of the
function, they'll be attributed to the end of the scope of the variable,
the same as the non-exceptional dtor call.

This doesn't /quite/ remove all uses of CurEHLocation (which might be
nice to remove, for a few reasons) - it's still used to choose the
location for some other work in the landing pad. It'd be nice to
attribute that code to the same location as the exception calls within
the block and to remove CurEHLocation.

llvm-svn: 228181
2015-02-04 19:47:54 +00:00
David Blaikie 303facbeb8 DebugInfo: Fix line table for comparisons harder/better for the sake of C (& the GDB buildbot)
llvm-svn: 227663
2015-01-31 01:10:11 +00:00
David Blaikie 298720d324 DebugInfo: Attribute implicit boolean tests to the expression being tested, not to the outer use of that expression.
This is half a fix for a GDB test suite failure that expects to start at
'a' in the following code:

  void func(int a)
    if (a
        &&
	b)
	...

But instead, without this change, the comparison was assigned to '&&'
(well, worse actually - because there was a chained 'a && b && c' and it
was assigned to the second '&&' because of a recursive application of
this bug) and then the load folded into the comparison so breaking on
the function started at '&&' instead of 'a'.

The other part of this needs to be fixed in LLVM where it's ignoring the
location of the icmp and instead using the location of the branch
instruction.

The fix to the conditional operator is actually a no-op currently,
because the conditional operator's location coincides with 'a' (the
start of the conditional expression) but should probably be '?' instead.
See the FIXME in the test case that mentions the ARCMigration tool
failures when I tried to make that change.

llvm-svn: 227356
2015-01-28 19:50:09 +00:00
Reid Kleckner 1d59f99f5c Initial support for Win64 SEH IR emission
The lowering looks a lot like normal EH lowering, with the exception
that the exceptions are caught by executing filter expression code
instead of matching typeinfo globals. The filter expressions are
outlined into functions which are used in landingpad clauses where
typeinfo would normally go.

Major aspects that still need work:
- Non-call exceptions in __try bodies won't work yet. The plan is to
  outline the __try block in the frontend to keep things simple.
- Filter expressions cannot use local variables until capturing is
  implemented.
- __finally blocks will not run after exceptions. Fixing this requires
  work in the LLVM SEH preparation pass.

The IR lowering looks like this:

// C code:
bool safe_div(int n, int d, int *r) {
  __try {
    *r = normal_div(n, d);
  } __except(_exception_code() == EXCEPTION_INT_DIVIDE_BY_ZERO) {
    return false;
  }
  return true;
}

; LLVM IR:
define i32 @filter(i8* %e, i8* %fp) {
  %ehptrs = bitcast i8* %e to i32**
  %ehrec = load i32** %ehptrs
  %code = load i32* %ehrec
  %matches = icmp eq i32 %code, i32 u0xC0000094
  %matches.i32 = zext i1 %matches to i32
  ret i32 %matches.i32
}

define i1 zeroext @safe_div(i32 %n, i32 %d, i32* %r) {
  %rr = invoke i32 @normal_div(i32 %n, i32 %d)
      to label %normal unwind to label %lpad

normal:
  store i32 %rr, i32* %r
  ret i1 1

lpad:
  %ehvals = landingpad {i8*, i32} personality i32 (...)* @__C_specific_handler
      catch i8* bitcast (i32 (i8*, i8*)* @filter to i8*)
  %ehptr = extractvalue {i8*, i32} %ehvals, i32 0
  %sel = extractvalue {i8*, i32} %ehvals, i32 1
  %filter_sel = call i32 @llvm.eh.seh.typeid.for(i8* bitcast (i32 (i8*, i8*)* @filter to i8*))
  %matches = icmp eq i32 %sel, %filter_sel
  br i1 %matches, label %eh.except, label %eh.resume

eh.except:
  ret i1 false

eh.resume:
  resume
}

Reviewers: rjmccall, rsmith, majnemer

Differential Revision: http://reviews.llvm.org/D5607

llvm-svn: 226760
2015-01-22 01:36:17 +00:00
David Blaikie 66e4197f07 Reapply r225000 (reverted in r225555): DebugInfo: Generalize debug info location handling (and follow-up commits).
Several pieces of code were relying on implicit debug location setting
which usually lead to incorrect line information anyway. So I've fixed
those (in r225955 and r225845) separately which should pave the way for
this commit to be cleanly reapplied.

The reason these implicit dependencies resulted in crashes with this
patch is that the debug location would no longer implicitly leak from
one place to another, but be set back to invalid. Once a call with
no/invalid location was emitted, if that call was ever inlined it could
produce invalid debugloc chains and assert during LLVM's codegen.

There may be further cases of such bugs in this patch - they're hard to
flush out with regression testing, so I'll keep an eye out for reports
and investigate/fix them ASAP if they come up.

Original commit message:

Reapply "DebugInfo: Generalize debug info location handling"

Originally committed in r224385 and reverted in r224441 due to concerns
this change might've introduced a crash. Turns out this change fixes the
crash introduced by one of my earlier more specific location handling
changes (those specific fixes are reverted by this patch, in favor of
the more general solution).

Recommitted in r224941 and reverted in r224970 after it caused a crash
when building compiler-rt. Looks to be due to this change zeroing out
the debug location when emitting default arguments (which were meant to
inherit their outer expression's location) thus creating call
instructions without locations - these create problems for inlining and
must not be created. That is fixed and tested in this version of the
change.

Original commit message:

This is a more scalable (fixed in mostly one place, rather than many
places that will need constant improvement/maintenance) solution to
several commits I've made recently to increase source fidelity for
subexpressions.

This resetting had to be done at the DebugLoc level (not the
SourceLocation level) to preserve scoping information (if the resetting
was done with CGDebugInfo::EmitLocation, it would've caused the tail end
of an expression's codegen to end up in a potentially different scope
than the start, even though it was at the same source location). The
drawback to this is that it might leave CGDebugInfo out of sync. Ideally
CGDebugInfo shouldn't have a duplicate sense of the current
SourceLocation, but for now it seems it does... - I don't think I'm
going to tackle removing that just now.

I expect this'll probably cause some more buildbot fallout & I'll
investigate that as it comes up.

Also these sort of improvements might be starting to show a weakness/bug
in LLVM's line table handling: we don't correctly emit is_stmt for
statements, we just put it on every line table entry. This means one
statement split over multiple lines appears as multiple 'statements' and
two statements on one line (without column info) are treated as one
statement.

I don't think we have any IR representation of statements that would
help us distinguish these cases and identify the beginning of each
statement - so that might be something we need to add (possibly to the
lexical scope chain - a scope for each statement). This does cause some
problems for GDB and possibly other DWARF consumers.

llvm-svn: 225956
2015-01-14 07:38:27 +00:00
David Blaikie f353d3ecd0 Revert "DebugInfo: Generalize debug info location handling" and related commits
This reverts commit r225000, r225021, r225083, r225086, r225090.

The root change (r225000) still has several issues where it's caused
calls to be emitted without debug locations. This causes assertion
failures if/when those calls are inlined.

I'll work up some test cases and fixes before recommitting this.

llvm-svn: 225555
2015-01-09 23:00:28 +00:00
David Blaikie b9a23c9155 DebugInfo: Provide a less subtle way to set the debug location of simple ret instructions
un-XFAILing the test XFAIL'd in r225086 after it regressed in r225083.

llvm-svn: 225090
2015-01-02 22:07:26 +00:00
Pekka Jaaskelainen 3701450b06 OpenCL C: Add support for a set of floating point
arithmetic relaxation flags:

-cl-no-signed-zeros
-cl-unsafe-math-optimizations
-cl-finite-math-only
-cl-fast-relaxed-math

Propagate the info to FP instruction flags as well
as function attributes where they are available.

llvm-svn: 223928
2014-12-10 16:41:14 +00:00