864 Commits

Author SHA1 Message Date
Filipe Cabecinhas
7af183d841 Propagate SourceLocations through to get a Loc on float_cast_overflow
Summary:
float_cast_overflow is the only UBSan check without a source location attached.
This patch propagates SourceLocations where necessary to get them to the
EmitCheck() call.

Reviewers: rsmith, ABataev, rjmccall

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D11757

llvm-svn: 244568
2015-08-11 04:19:28 +00:00
Benjamin Kramer
9938310ab3 [CodeGen] Simplify creation of shuffle masks.
No functional change intended.

llvm-svn: 243439
2015-07-28 16:25:32 +00:00
David Blaikie
f05779e21c Pass an iterator range to EmitCallArgs
llvm-svn: 242824
2015-07-21 18:37:18 +00:00
David Blaikie
4ba525b727 Rely on default zero-arg value for IRBuilder::CreateCall calls to zero-arg functions
Patch by servuswiegehtz at yahoo.de

llvm-svn: 242168
2015-07-14 17:27:39 +00:00
Ulrich Weigand
03ce2a16bf Respect alignment of nested bitfields
tools/clang/test/CodeGen/packed-nest-unpacked.c contains this test:

struct XBitfield {
  unsigned b1 : 10;
  unsigned b2 : 12;
  unsigned b3 : 10;
};
struct YBitfield {
  char x;
  struct XBitfield y;
} __attribute((packed));
struct YBitfield gbitfield;

unsigned test7() {
  // CHECK: @test7
  // CHECK: load i32, i32* getelementptr inbounds (%struct.YBitfield, %struct.YBitfield* @gbitfield, i32 0, i32 1, i32 0), align 4
  return gbitfield.y.b2;
}

The "align 4" is actually wrong.  Accessing all of "gbitfield.y" as a single
i32 is of course possible, but that still doesn't make it 4-byte aligned as
it remains packed at offset 1 in the surrounding gbitfield object.

This alignment was changed by commit r169489, which also introduced changes
to bitfield access code in CGExpr.cpp.  Code before that change used to take
into account *both* the alignment of the field to be accessed within the
current struct, *and* the alignment of that outer struct itself; this logic
was removed by the above commit.

Neglecting to consider both values can cause incorrect code to be generated
(I've seen an unaligned access crash on SystemZ due to this bug).

In order to always use the best known alignment value, this patch removes
the CGBitFieldInfo::StorageAlignment member and replaces it with a
StorageOffset member specifying the offset from the start of the surrounding
struct to the bitfield's underlying storage.  This offset can then be combined
with the best-known alignment for a bitfield access lvalue to determine the
alignment to use when accessing the bitfield's storage.

Differential Revision: http://reviews.llvm.org/D11034

llvm-svn: 241916
2015-07-10 17:30:00 +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
Alexander Kornienko
ab9db51042 Revert r240270 ("Fixed/added namespace ending comments using clang-tidy").
llvm-svn: 240353
2015-06-22 23:07:51 +00:00
Alexander Kornienko
3d9d929e42 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

  $ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
      -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
      work/llvm/tools/clang

To reduce churn, not touching namespaces spanning less than 10 lines.

llvm-svn: 240270
2015-06-22 09:47:44 +00:00
Peter Collingbourne
6708c4a176 Implement diagnostic mode for -fsanitize=cfi*, -fsanitize=cfi-diag.
This causes programs compiled with this flag to print a diagnostic when
a control flow integrity check fails instead of aborting. Diagnostics are
printed using UBSan's runtime library.

The main motivation of this feature over -fsanitize=vptr is fidelity with
the -fsanitize=cfi implementation: the diagnostics are printed under exactly
the same conditions as those which would cause -fsanitize=cfi to abort the
program. This means that the same restrictions apply regarding compiling
all translation units with -fsanitize=cfi, cross-DSO virtual calls are
forbidden, etc.

Differential Revision: http://reviews.llvm.org/D10268

llvm-svn: 240109
2015-06-19 01:51:54 +00:00
Peter Collingbourne
9881b78b53 Introduce -fsanitize-trap= flag.
This flag controls whether a given sanitizer traps upon detecting
an error. It currently only supports UBSan. The existing flag
-fsanitize-undefined-trap-on-error has been made an alias of
-fsanitize-trap=undefined.

This change also cleans up some awkward behavior around the combination
of -fsanitize-trap=undefined and -fsanitize=undefined. Previously we
would reject command lines containing the combination of these two flags,
as -fsanitize=vptr is not compatible with trapping. This required the
creation of -fsanitize=undefined-trap, which excluded -fsanitize=vptr
(and -fsanitize=function, but this seems like an oversight).

Now, -fsanitize=undefined is an alias for -fsanitize=undefined-trap,
and if -fsanitize-trap=undefined is specified, we treat -fsanitize=vptr
as an "unsupported" flag, which means that we error out if the flag is
specified explicitly, but implicitly disable it if the flag was implied
by -fsanitize=undefined.

Differential Revision: http://reviews.llvm.org/D10464

llvm-svn: 240105
2015-06-18 23:59:22 +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
3eea677f3a Unify sanitizer kind representation between the driver and the rest of the compiler.
No functional change.

Differential Revision: http://reviews.llvm.org/D9618

llvm-svn: 237055
2015-05-11 21:39:14 +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
Benjamin Kramer
f3e67de85a [CodeGen] Do a more principled fix for PR231653, always use the inner type.
We were still using the MaterializeTemporaryExpr's type to check if the
transform is legal. Always use the inner Expr type.

llvm-svn: 234543
2015-04-09 22:50:07 +00:00
Benjamin Kramer
b2b81439a3 [CodeGen] When promoting a reference temporary to a global use the inner type to fold it.
The MaterializeTemporaryExpr can have a different type than the inner
expression, miscompiling the constant. PR23165.

llvm-svn: 234499
2015-04-09 16:09:29 +00:00
David Blaikie
2e80428dc5 clang-format my last commit
(sorry, keep forgetting that)

llvm-svn: 234129
2015-04-05 22:47:07 +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
17ea266bac [opaque pointer type] More GEP API migrations
llvm-svn: 234109
2015-04-04 21:07:17 +00:00
Nick Lewycky
84146bee6c Fix the LLVM type used when lowering initializer list reference temporaries to global variables. Reapplies r232454 with fix for PR22940.
llvm-svn: 232579
2015-03-18 01:06:24 +00:00
Hans Wennborg
f9d865b059 Revert r232454 and r232456: "Fix the LLVM type used when lowering initializer list reference temporaries to global variables."
This caused PR22940.

llvm-svn: 232496
2015-03-17 16:38:58 +00:00
Nick Lewycky
cf191adaf5 Fix the LLVM type used when lowering initializer list reference temporaries to global variables.
llvm-svn: 232454
2015-03-17 02:21:31 +00:00
Peter Collingbourne
d2926c91d5 Implement bad cast checks using control flow integrity information.
This scheme checks that pointer and lvalue casts are made to an object of
the correct dynamic type; that is, the dynamic type of the object must be
a derived class of the pointee type of the cast. The checks are currently
only introduced where the class being casted to is a polymorphic class.

Differential Revision: http://reviews.llvm.org/D8312

llvm-svn: 232241
2015-03-14 02:42:25 +00:00
Benjamin Kramer
f8b86964ca Reapply r231508 "CodeGen: Emit constant temporaries into read-only globals."
I disabled putting the new global into the same COMDAT as the function for now.
There's a fundamental problem when we inline references to the global but still
have the global in a COMDAT linked to the inlined function. Since this is only
an optimization there may be other versions of the COMDAT around that are
missing the new global and hell breaks loose at link time.

I hope the chromium build doesn't break this time :)

llvm-svn: 231564
2015-03-07 13:37:13 +00:00
Hans Wennborg
cd8f011157 Revert r231508 "CodeGen: Emit constant temporaries into read-only globals."
This broke the Chromium build. Links were failing with messages like:

obj/dbus/libdbus_test_support.a(obj/dbus/dbus_test_support.mock_object_proxy.o):../../dbus/mock_object_proxy.cc:function dbus::MockObjectProxy::Detach(): warning: relocation refers to discarded section
/usr/local/google/work/chromium/src/third_party/binutils/Linux_x64/Release/bin/ld.gold: error: treating warnings as errors

llvm-svn: 231541
2015-03-07 00:46:19 +00:00
Benjamin Kramer
3d8aa5c77d CodeGen: Emit constant temporaries into read-only globals.
Instead of creating a copy on the stack just stash them in a private
constant global. This saves both the copying overhead and the stack
space, and gives the optimizer more room to constant fold.

This tries to make array temporaries more similar to regular arrays,
they can't use the same logic because a temporary has no VarDecl to be
bound to so we roll our own version here.

The original use case for this optimization was code like
  for (int i : {1, 2, 3, 4, 5, 6, 7, 8, 10})
    foo(i);
where without this patch (assuming that the loop is not unrolled) we
would alloca an array on the stack, copy the 10 values over and
iterate on that. With this patch we put the array in .text use it
directly. Apart from that case this helps on virtually any passing of
a constant std::initializer_list as a function argument.

Differential Revision: http://reviews.llvm.org/D8034

llvm-svn: 231508
2015-03-06 20:00:03 +00:00
David Majnemer
ced8bdf74a Sema: Parenthesized bound destructor member expressions can be called
We would wrongfully reject (a.~A)() in both the destructor and
pseudo-destructor cases.

This fixes PR22668.

llvm-svn: 230512
2015-02-25 17:36:15 +00:00
Alexey Bataev
3eff5f46d7 [OPENMP] Rename methods of OpenMPRuntime class. NFC.
llvm-svn: 230470
2015-02-25 08:32:46 +00:00
David Majnemer
eeaec26534 Try to unbreak the Hexagon bot
llvm-svn: 229219
2015-02-14 02:18:14 +00:00
David Majnemer
ce27e42d47 CodeGen: _Atomic(_Complex) shouldn't crash
We could be a little kinder if we did a compare-exchange loop instead of
an atomic-load/store pair.

llvm-svn: 229212
2015-02-14 01:48:17 +00:00
David Majnemer
a5b195a1dc Revert "Revert r229082 for a bit, it caused PR22577."
This reverts commit r229123.  It was a red herring, the bug was present
without r229082.

llvm-svn: 229205
2015-02-14 01:35:12 +00:00
David Majnemer
6866a3c6f4 CodeGen: Correctly convert atomic bool from i8 to i1
Bools are a little tricky, they are i8 in memory and must be coerced
back to i1 before further operations can be performed on them.

This fixes PR22577.

llvm-svn: 229204
2015-02-14 01:35:07 +00:00
Nico Weber
7ce96b853d Revert r229082 for a bit, it caused PR22577.
llvm-svn: 229123
2015-02-13 16:27:00 +00:00
David Majnemer
abc482effc MS ABI: Implement /volatile:ms
The /volatile:ms semantics turn volatile loads and stores into atomic
acquire and release operations.  This distinction is important because
volatile memory operations do not form a happens-before relationship
with non-atomic memory.  This means that a volatile store is not
sufficient for implementing a mutex unlock routine.

Differential Revision: http://reviews.llvm.org/D7580

llvm-svn: 229082
2015-02-13 07:55:47 +00:00
David Blaikie
9f7ae2c948 DebugInfo: Attribute calls to overloaded operators with the operator, not the start of the whole expression
llvm-svn: 227028
2015-01-25 01:25:37 +00:00
David Blaikie
9b47966615 DebugInfo: Use the preferred location rather than the start location for expression line info
This causes things like assignment to refer to the '=' rather than the
LHS when attributing the store instruction, for example.

There were essentially 3 options for this:

* The beginning of an expression (this was the behavior prior to this
  commit). This meant that stepping through subexpressions would bounce
  around from subexpressions back to the start of the outer expression,
  etc. (eg: x + y + z would go x, y, x, z, x (the repeated 'x's would be
  where the actual addition occurred)).

* The end of an expression. This seems to be what GCC does /mostly/, and
  certainly this for function calls. This has the advantage that
  progress is always 'forwards' (never jumping backwards - except for
  independent subexpressions if they're evaluated in interesting orders,
  etc). "x + y + z" would go "x y z" with the additions occurring at y
  and z after the respective loads.
  The problem with this is that the user would still have to think
  fairly hard about precedence to realize which subexpression is being
  evaluated or which operator overload is being called in, say, an asan
  backtrace.

* The preferred location or 'exprloc'. In this case you get sort of what
  you'd expect, though it's a bit confusing in its own way due to going
  'backwards'. In this case the locations would be: "x y + z +" in
  lovely postfix arithmetic order. But this does mean that if the op+
  were an operator overload, say, and in a backtrace, the backtrace will
  point to the exact '+' that's being called, not to the end of one of
  its operands.

(actually the operator overload case doesn't work yet for other reasons,
but that's being fixed - but this at least gets scalar/complex
assignments and other plain operators right)

llvm-svn: 227027
2015-01-25 01:19:10 +00:00
David Blaikie
2d321fb79d DebugInfo: Correct the line location of geps on array accesses
llvm-svn: 227023
2015-01-24 23:35:17 +00:00
David Blaikie
a1fd099575 DebugInfo: Remove outdated comment. Column info is no longer needed to differentiate inline callsites.
llvm-svn: 226955
2015-01-23 22:48:27 +00:00
David Blaikie
835afb205f DebugInfo: Remove forced column-info workaround for inlined calls
This workaround was to provide unique call sites to ensure LLVM's inline
debug info handling would properly unique two calls to the same function
on the same line. Instead, this has now been fixed in LLVM (r226736) and
the workaround here can be removed.

Originally committed in r176895, but this isn't a straight revert due to
all the changes since then. I just searched for anything ForcedColumn*
related and removed them.

We could test this - but it didn't strike me as terribly valuable once
we're no longer adding this workaround everything just works as expected
& it's no longer a special case to test for.

llvm-svn: 226738
2015-01-21 23:08:17 +00:00
Chandler Carruth
0d9593ddec [cleanup] Re-sort *all* #include lines with llvm/utils/sort_includes.py
Sorry for the noise, I managed to miss a bunch of recent regressions of
include orderings here. This should actually sort all the includes for
Clang. Again, no functionality changed, this is just a mechanical
cleanup that I try to run periodically to keep the #include lines as
regular as possible across the project.

llvm-svn: 225979
2015-01-14 11:29:14 +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
Alexey Samsonov
8845952b54 Reimplement -fsanitize-recover family of flags.
Introduce the following -fsanitize-recover flags:
  - -fsanitize-recover=<list>: Enable recovery for selected checks or
      group of checks. It is forbidden to explicitly list unrecoverable
      sanitizers here (that is, "address", "unreachable", "return").
  - -fno-sanitize-recover=<list>: Disable recovery for selected checks or
     group of checks.
  - -f(no-)?sanitize-recover is now a synonym for
    -f(no-)?sanitize-recover=undefined,integer and will soon be deprecated.

These flags are parsed left to right, and mask of "recoverable"
sanitizer is updated accordingly, much like what we do for -fsanitize= flags.
-fsanitize= and -fsanitize-recover= flag families are independent.

CodeGen change: If there is a single UBSan handler function, responsible
for implementing multiple checks, which have different recoverable setting,
then we emit two handler calls instead of one:
the first one for the set of "unrecoverable" checks, another one - for
set of "recoverable" checks. If all checks implemented by a handler have the
same recoverability setting, then the generated code will be the same.

llvm-svn: 225719
2015-01-12 22:39:12 +00:00
Alexey Bataev
19acc3d351 Rename RefersToCapturedVariable to RefersToEnclosingVariableOrCapture, NFC
llvm-svn: 225624
2015-01-12 10:17:46 +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 Majnemer
602cfe7d62 CodeGen: Don't crash when a lambda uses a local constexpr variable
The DeclRefExpr might be for a variable initialized by a constant
expression which hasn't been ODR used.
Emit the initializer for the variable instead of trying to capture the
variable itself.

This fixes PR22071.

llvm-svn: 225060
2015-01-01 09:49:44 +00:00
David Blaikie
84fe79cfc3 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: 225000
2014-12-30 19:39:33 +00:00
David Blaikie
608a24501c Revert "DebugInfo: Generalize debug info location handling"
Asserting when building compiler-rt when using a GCC host compiler.
Reverting while I investigate.

This reverts commit r224941.

llvm-svn: 224970
2014-12-29 23:49:00 +00:00
David Blaikie
3945d1bd99 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).

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: 224941
2014-12-29 18:18:45 +00:00
David Blaikie
06b2c54db9 Revert "DebugInfo: Generalize debug info location handling"
Fails an ASan bootstrap - I'll try to reproduce locally & sort that out
before recommitting.

This reverts commit r224385.

llvm-svn: 224441
2014-12-17 18:02:04 +00:00
David Blaikie
bf22a4eaee DebugInfo: Generalize debug info location handling
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: 224385
2014-12-16 22:49:17 +00:00
Alexey Bataev
07649fb7c5 Renamed RefersToEnclosingLocal bitfield to RefersToCapturedVariable.
Bitfield RefersToEnclosingLocal of Stmt::DeclRefExprBitfields renamed to RefersToCapturedVariable to reflect latest changes introduced in commit 224323. Also renamed method Expr::refersToEnclosingLocal() to Expr::refersToCapturedVariable() and comments for constant arguments.
No functional changes.

llvm-svn: 224329
2014-12-16 08:01:48 +00:00