Commit Graph

2683 Commits

Author SHA1 Message Date
Eric Christopher
3a3941576d Temporarily revert "Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information." as it appears to be breaking some LTO constructs.
This reverts commit r212203.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212298 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-03 22:24:54 +00:00
Ulrich Weigand
1ef2cec146 Fix ppcf128 component access on little-endian systems
The PowerPC 128-bit long double data type (ppcf128 in LLVM) is in fact a
pair of two doubles, where one is considered the "high" or
more-significant part, and the other is considered the "low" or
less-significant part.  When a ppcf128 value is stored in memory or a
register pair, the high part always comes first, i.e. at the lower
memory address or in the lower-numbered register, and the low part
always comes second.  This is true both on big-endian and little-endian
PowerPC systems.  (Similar to how with a complex number, the real part
always comes first and the imaginary part second, no matter the byte
order of the system.)

This was implemented incorrectly for little-endian systems in LLVM.
This commit fixes three related issues:

- When printing an immediate ppcf128 constant to assembler output
  in emitGlobalConstantFP, emit the high part first on both big-
  and little-endian systems.

- When lowering a ppcf128 type to a pair of f64 types in SelectionDAG
  (which is used e.g. when generating code to load an argument into a
  register pair), use correct low/high part ordering on little-endian
  systems.

- In a related issue, because lowering ppcf128 into a pair of f64 must
  operate differently from lowering an int128 into a pair of i64,
  bitcasts between ppcf128 and int128 must not be optimized away by the
  DAG combiner on little-endian systems, but must effect a word-swap.

Reviewed by Hal Finkel.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212274 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-03 15:06:47 +00:00
David Blaikie
231537a2fa Revert "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."
This reverts commit r212205.

Reverting this again, still seeing crashes when building compiler-rt...
Sorry for the continued noise, not sure why I'm failing to reproduce
this locally.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212226 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-02 21:42:28 +00:00
David Blaikie
a42211335a DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.
Originally committed in r211723, reverted in r211724 due to failure
cases found and fixed (ArgumentPromotion: r211872, Inlining: r212065),
committed again in r212085 and reverted again in r212089 after fixing
some other cases, such as debug info subprogram lists not keeping track
of the function they represent (r212128) and then short-circuiting
things like LiveDebugVariables that build LexicalScopes for functions
that might not have full debug info.

And again, I believe the invariant actually holds for some reasonable
amount of code (but I'll keep an eye on the buildbots and see what
happens... ).

Original commit message:

PR20038: DebugInfo: Inlined call sites where the caller has debug info
but the call itself has no debug location.

This situation does bad things when inlined, so I've fixed Clang not to
produce inlinable call sites without locations when the caller has debug
info (in the one case where I could find that this occurred). This
updates the PR20038 test case to be what clang now produces, and readds
the assertion that had to be removed due to this bug.

I've also beefed up the debug info verifier to help diagnose these
issues in the future, and I hope to add checks to the inliner to just
assert-fail if it encounters this situation. If, in the future, we
decide we have to cope with this situation, the right thing to do is
probably to just remove all the DebugLocs from the inlined instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212205 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-02 18:32:05 +00:00
David Blaikie
f9b6d0373a Don't try to construct debug LexicalScopes hierarchy for functions that do not have top level debug information.
If a function isn't actually in a CU's subprogram list in the debug info
metadata, ignore all the DebugLocs and don't try to build scopes, track
variables, etc.

While this is possibly a minor optimization, it's also a correctness fix
for an incoming patch that will add assertions to LexicalScopes and the
debug info verifier to ensure that all scope chains lead to debug info
for the current function.

Fix up a few test cases that had broken/incomplete debug info that could
violate this constraint.

Add a test case where this occurs by design (inlining a
debug-info-having function in an attribute nodebug function - we want
this to work because /if/ the nodebug function is then inlined into a
debug-info-having function, it should be fine (and will work fine - we
just stitch the scopes up as usual), but should the inlining not happen
we need to not assert fail either).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212203 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-02 18:31:35 +00:00
David Blaikie
74ed21faef Revert "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."
This reverts commit r212085.

This breaks the sanitizer bot... & I thought I'd tried pretty hard not
to do that. Guess I need to try harder.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212089 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-01 04:11:45 +00:00
David Blaikie
7186dd4513 DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.
Originally committed in r211723, reverted in r211724 due to failure
cases found and fixed (ArgumentPromotion: r211872, Inlining: r212065),
and I now believe the invariant actually holds for some reasonable
amount of code (but I'll keep an eye on the buildbots and see what
happens... ).

Original commit message:

PR20038: DebugInfo: Inlined call sites where the caller has debug info
but the call itself has no debug location.

This situation does bad things when inlined, so I've fixed Clang not to
produce inlinable call sites without locations when the caller has debug
info (in the one case where I could find that this occurred). This
updates the PR20038 test case to be what clang now produces, and readds
the assertion that had to be removed due to this bug.

I've also beefed up the debug info verifier to help diagnose these
issues in the future, and I hope to add checks to the inliner to just
assert-fail if it encounters this situation. If, in the future, we
decide we have to cope with this situation, the right thing to do is
probably to just remove all the DebugLocs from the inlined instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212085 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-01 03:11:59 +00:00
Saleem Abdulrasool
36c789f00e CodeGen: rename Win64 ExceptionHandling to WinEH
This exception format is not specific to Windows x64.  A similar approach is
taken on nearly all architectures.  Generalise the name to reflect reality.
This will eventually be used for Windows on ARM data emission as well.

Switch the enum and namespace into an enum class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212000 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-29 21:43:47 +00:00
Saleem Abdulrasool
622520e70f MC: rename EmitWin64EH routines
Rename the routines to reflect the reality that they are more related to call
frame information than to Win64 EH. Although EH is implemented in an intertwined
manner by augmenting with an exception handler and an associated parameter, the
majority of these routines emit information required to unwind the frames. This
also helps identify that these routines are generic for most windows platforms
(they apply equally to nearly all architectures except x86) although the
encoding of the information is architecture dependent.

Unwinding data is emitted via EmitWinCFI* and exception handling information via
EmitWinEH*.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211994 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-29 01:52:01 +00:00
David Blaikie
0263debd04 Revert "Revert "Revert "PR20038: DebugInfo: Inlined call sites where the caller has debug info but the call itself has no debug location."""
Reverting this again, didn't mean to commit it - while r211872 fixes one
of the issues here, there are still others to figure out and address.

This reverts commit r211871.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211873 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-27 05:34:05 +00:00
David Blaikie
150f5b8920 Revert "Revert "PR20038: DebugInfo: Inlined call sites where the caller has debug info but the call itself has no debug location.""
This reverts commit r211724.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211871 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-27 05:31:49 +00:00
Alp Toker
8dd8d5c2b2 Revert "Introduce a string_ostream string builder facilty"
Temporarily back out commits r211749, r211752 and r211754.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211814 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-26 22:52:05 +00:00
Alp Toker
2559070422 Introduce a string_ostream string builder facilty
string_ostream is a safe and efficient string builder that combines opaque
stack storage with a built-in ostream interface.

small_string_ostream<bytes> additionally permits an explicit stack storage size
other than the default 128 bytes to be provided. Beyond that, storage is
transferred to the heap.

This convenient class can be used in most places an
std::string+raw_string_ostream pair or SmallString<>+raw_svector_ostream pair
would previously have been used, in order to guarantee consistent access
without byte truncation.

The patch also converts much of LLVM to use the new facility. These changes
include several probable bug fixes for truncated output, a programming error
that's no longer possible with the new interface.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211749 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-26 00:00:48 +00:00
David Blaikie
276ef73f4a Revert "PR20038: DebugInfo: Inlined call sites where the caller has debug info but the call itself has no debug location."
This reverts commit r211723.

Breaks the ASan/compiler-rt build... guess I didn't test very far at all
:/.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211724 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-25 18:20:54 +00:00
David Blaikie
c39f36df61 PR20038: DebugInfo: Inlined call sites where the caller has debug info but the call itself has no debug location.
This situation does bad things when inlined, so I've fixed Clang not to
produce inlinable call sites without locations when the caller has debug
info (in the one case where I could find that this occurred). This
updates the PR20038 test case to be what clang now produces, and readds
the assertion that had to be removed due to this bug.

I've also beefed up the debug info verifier to help diagnose these
issues in the future, and I hope to add checks to the inliner to just
assert-fail if it encounters this situation. If, in the future, we
decide we have to cope with this situation, the right thing to do is
probably to just remove all the DebugLocs from the inlined instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211723 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-25 18:03:10 +00:00
NAKAMURA Takumi
b720a3d15c Re-apply r211399, "Generate native unwind info on Win64" with a fix to ignore SEH pseudo ops in X86 JIT emitter.
--
This patch enables LLVM to emit Win64-native unwind info rather than
DWARF CFI.  It handles all corner cases (I hope), including stack
realignment.

Because the unwind info is not flexible enough to describe stack frames
with a gap of unknown size in the middle, such as the one caused by
stack realignment, I modified register spilling code to place all spills
into the fixed frame slots, so that they can be accessed relative to the
frame pointer.

Patch by Vadim Chugunov!

Reviewed By: rnk

Differential Revision: http://reviews.llvm.org/D4081

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211691 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-25 12:41:52 +00:00
Rafael Espindola
4186005edc Print a=b as an assignment.
In assembly the expression a=b is parsed as an assignment, so it should be
printed as one.

This remove a truly horrible hack for producing a label with "a=.". It would
be used by codegen but would never be reached by the asm parser. Sorry I
missed this when it was first committed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211639 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-24 22:45:16 +00:00
Rafael Espindola
0de4a6b17d Remove a temporary hack.
Amusingly this survived a lot longer than the CFI transition. We don't even
support non-cfi assemblers any more.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211498 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-23 14:22:55 +00:00
NAKAMURA Takumi
9124b45918 Revert r211399, "Generate native unwind info on Win64"
It broke Legacy JIT Tests on x86_64-{mingw32|msvc}, aka Windows x64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211480 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-22 22:00:56 +00:00
Richard Trieu
7921239c41 Add back functionality removed in r210497.
Instead of asserting, output a message stating that a null pointer was found.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211430 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-21 02:43:02 +00:00
Reid Kleckner
5b8e73ef81 Generate native unwind info on Win64
This patch enables LLVM to emit Win64-native unwind info rather than
DWARF CFI.  It handles all corner cases (I hope), including stack
realignment.

Because the unwind info is not flexible enough to describe stack frames
with a gap of unknown size in the middle, such as the one caused by
stack realignment, I modified register spilling code to place all spills
into the fixed frame slots, so that they can be accessed relative to the
frame pointer.

Patch by Vadim Chugunov!

Reviewed By: rnk

Differential Revision: http://reviews.llvm.org/D4081

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211399 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-20 20:35:47 +00:00
Yaron Keren
ed4e8a839f The count() function for STL datatypes returns unsigned, even where it's
only 1/0 result like std::set. Some of the LLVM ADT already return unsigned
count(), while others still return bool count().

In continuation to r197879, this patch modifies DenseMap, DenseSet, 
ScopedHashTable, ValueMap:: count() to return size_type instead of bool,
1 instead of true and 0 instead of false.

size_type is typedef-ed locally within each class to size_t.

http://reviews.llvm.org/D4018

Reviewed by dblaikie.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211350 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-20 10:26:56 +00:00
David Blaikie
6072096fd6 DebugInfo: Fission: Ensure the address pool entries for location lists are emitted.
The address pool was being emitted before location lists. The latter
could add more entries to the pool which would be lost/never emitted.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211284 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 17:59:14 +00:00
Oliver Stannard
bb804ee909 Emit DWARF3 call frame information when DWARF3+ debug info is requested
Currently, llvm always emits a DWARF CIE with a version of 1, even when emitting
DWARF 3 or 4, which both support CIE version 3. This patch makes it emit the
newer CIE version when we are emitting DWARF 3 or 4. This will not reduce
compatibility, as we already emit other DWARF3/4 features, and is worth doing as
the DWARF3 spec removed some ambiguities in the interpretation of call frame
information.

It also fixes a minor bug where the "return address" field of the CIE was
encoded as a ULEB128, which is only valid when the CIE version is 3. There are
no test changes for this, because (as far as I can tell) none of the platforms
that we test have a return address register with a DWARF register number >127.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211272 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 15:39:33 +00:00
Eric Christopher
179bb4e0ee Move -dwarf-version to an MC level command line option so it's
used by all of the MC level tools and codegen. Fix up all uses
in the compiler to use this and set it on the context accordingly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211257 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 06:22:08 +00:00
Eric Christopher
054bd5d288 Remove unnecessary include.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211256 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-19 06:22:05 +00:00
David Blaikie
5379c6930d PR20038: DebugInfo missing DIEs for some concrete variables.
I haven't nailed this down entirely, but this is about as small of a
test case as I can seem to construct and adequately demonstrates the
crasher. I'll continue investigating the root cause/fix(es).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210993 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-15 19:34:26 +00:00
David Blaikie
d32eccc97b DebugInfo: Remove some extra handling of abstract variables and instead rely solely on the delayed handling introduced in r210946
Now that we handle finding abstract variables at the end of the module,
remove the upfront handling and just ensure the abstract variable is
built when necessary.

In theory we could have a split implementation, where inlined variables
are immediately constructed referencing the abstract definition, and
concrete variables are delayed - but let's go with one solution for now
unless there's a reason not to.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210961 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-13 23:52:55 +00:00
David Blaikie
f154f3b592 DebugInfo: Reference abstract definitions from variables in concrete definitions that preceed their first inline definition.
Rather than relying on abstract variables looked up at the time the
concrete variable is created, look them up at the end of the module to
ensure they're referenced even if they're created after the concrete
definition. This completes/matches the work done in r209677 to handle
this for the subprograms themselves.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210946 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-13 22:35:44 +00:00
David Blaikie
9907af99d4 DwarfDebug::getExistingAbstractVariable: constify an existing reference parameter that didn't need to be mutated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210944 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-13 22:29:31 +00:00
David Blaikie
0fcb9cb1c1 DebugInfo: Following up to r209677, refactor local variable emission to delay the choice between emitting the definition attributes or using DW_AT_abstract_definition
This doesn't fix the abstract variable handling yet, but it introduces a
similar delay mechanism as was added for subprograms, causing
DW_AT_location to be reordered to the beginning of the attribute list
for local variables, and fixes all the test fallout for that.

A subsequent commit will remove the abstract variable handling in
DbgVariable and just do the abstract variable lookup at module end to
ensure that abstract variables introduced after their concrete
counterparts are appropriately referenced by the concrete variable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210943 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-13 22:18:23 +00:00
Saleem Abdulrasool
095271bcf4 CodeGen: refactor DwarfException
DwarfException served as a base class for exception handling directive emission.
However, this is also used by other exception models (e.g. Win64EH).  Rename
this class to EHStreamer and split it out of DwarfException.h.  NFC.

Use the opportunity to fix up some of the documentation comments to match
current LLVM style.  Also rename some functions to conform better with current
LLVM coding style.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210622 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-11 01:19:03 +00:00
Richard Trieu
f31ecd3927 Removing an "if (!this)" check from two print methods. The condition will
never be true in a well-defined context.  The checking for null pointers
has been moved into the caller logic so it does not rely on undefined behavior.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210497 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-09 22:53:16 +00:00
Alexey Samsonov
f4a702c079 Generate better location ranges for some register-described variables.
Don't terminate location ranges for register-described variables
at the end of machine basic block if this register is never modified
in the function body, except for the prologue and epilogue. Prologue
location is guessed by FrameSetup flags on MachineInstructions, while
epilogue location is deduced from debug locations of instructions
in the basic blocks ending with return instructions.

This patch is mostly targeted to fix non-trivial debug locations for
variables addressed via stack and frame pointers.

It is not really a generic fix. We can still produce poor debug info
for register-described variables if this register *is* modified somewhere
in the function, but in unrelated places. This might be the case for the debug
info in optimized binaries (e.g. for local variables in inlined functions).
LiveDebugVariables pass in CodeGen attempts to fix this problem by adjusting
DBG_VALUE instructions, but this pass is tied to greedy register allocator,
which is used in optimized builds only. Proper fix would likely involve
generalizing LiveDebugVariables to all register allocators. See more discussion
in http://reviews.llvm.org/D3933 review thread.

I'm proceeding with this patch to fix immediate severe problems and
important cases, e.g. fix completely broken debug info with AddressSanitizer
and fix PR19307 (missing debug info for by-value std::string arguments).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210492 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-09 21:53:47 +00:00
Alp Toker
3c9b41b949 Fix typos
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210401 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-07 21:23:09 +00:00
David Blaikie
8ef9d22f5b DebugInfo: Use the scope of the function declaration, if any, to name a function in DWARF pubnames
This ensures that member functions, for example, are entered into
pubnames with their fully qualified name, rather than inside the global
namespace.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210379 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-06 22:29:05 +00:00
David Blaikie
ebcf48cf9e DebugInfo: pubnames: include file-local (static or anonymous namespace) variables and anonymous namespaces themselves.
Still some issues with name qualification, FIXMEs added to test cases
and fixes will come next.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210378 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-06 22:16:56 +00:00
Rafael Espindola
013321a0f9 Fix a few issues with comdat handling on COFF.
* Section association cannot use just the section name as many
sections can have the same name. With this patch, the comdat symbol in
an assoc section is interpreted to mean a symbol in the associated
section and the mapping is discovered from it.

* Comdat symbols were not being set correctly. Instead we were getting
whatever was output first for that section.

A consequence is that associative sections now must use .section to
set the association. Using .linkonce would not work since it is not
possible to change a sections comdat symbol (it is used to decide if
we should create a new section or reuse an existing one).

This includes r210298, which was reverted because it was asserting
on an associated section having the same comdat as the associated
section.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210367 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-06 19:26:12 +00:00
Alexey Samsonov
3b889b9d31 Fix null dereference with -debug-only=dwarfdebug
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210299 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 23:10:19 +00:00
Tom Roeder
5d0f7af3dc Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.
It includes a pass that rewrites all indirect calls to jumptable functions to pass through these tables.

This also adds backend support for generating the jump-instruction tables on ARM and X86.
Note that since the jumptable attribute creates a second function pointer for a
function, any function marked with jumptable must also be marked with unnamed_addr.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210280 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 19:29:43 +00:00
David Blaikie
0bc7690e34 Revert r210221 again, due to a crash Richard Smith has provided involving self-hosting LLVM with libc++.
Test case coming, once I reduce it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210236 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 02:04:59 +00:00
David Blaikie
7a986ec4de DebugInfo: Reuse existing LexicalScope to retrieve the scope's MDNode, rather than looking it up through the DebugLoc.
No functional change intended, just streamlines the abstract variable
lookup/construction to use a common entry point.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210234 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 01:30:50 +00:00
David Blaikie
75096077d4 DebugInfo: Roll argument insertion into variable insertion to ensure arguments are correctly handled in all cases.
No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210233 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 01:04:20 +00:00
David Blaikie
ad03fa6d3f PR19388: DebugInfo: Emit dead arguments in their originally declared order.
Unused arguments were not being added to the argument list, but instead
treated as arbitrary scope variables. This meant they weren't carefully
added in the original argument order.

In this particular example, though, it turns out the argument is only
/mostly/ unused (well, actually it's entirely used, but in a specific
way). It's a struct that, due to ABI reasons, is decomposed into chunks
(exactly one chunk, since it has one member) and then passed. Since only
one of those chunks is used (SROA, etc, kill the original reconstitution
code) we don't have a location to describe the whole variable.

In this particular case, since the struct consists of just the one int,
once we have partial location information, this should have a location
that describes the entire variable (since the piece is the entirety of
the object).

And at some point we'll need to describe the location of even /entirely/
unused arguments so that they can at least be printed on function entry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210231 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 00:51:35 +00:00
David Blaikie
d4af856cfb DebugInfo: Add comments/assert description to r209674 based on Eric Christopher's post-commit review feedback.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210228 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 00:25:26 +00:00
David Blaikie
06ac3ffc8f DebugInfo: Reapply r209984 (reverted in r210143), asserting that abstract DbgVariables have DIEs.
Abstract variables within abstract scopes that are entirely optimized
away in their first inlining are omitted because their scope is not
present so the variable is never created. Instead, we should ensure the
scope is created so the variable can be added, even if it's been
optimized away in its first inlining.

This fixes the incorrect debug info in missing-abstract-variable.ll
(added in r210143) and passes an asserts self-hosting build, so
hopefully there's not more of these issues left behind... *fingers
crossed*.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210221 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-04 23:50:52 +00:00
Hans Wennborg
6248abf28d Don't emit structors for available_externally globals (PR19933)
We would previously assert here when trying to figure out the section
for the global.

This makes us handle the situation more gracefully since the IR isn't
malformed.

Differential Revision: http://reviews.llvm.org/D4022

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210215 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-04 21:04:54 +00:00
David Blaikie
5c0b13f3be DebugInfo: Partial revert r209984 due to more cases where abstract DbgVariables do not have associated DIEs.
Along with a test case to demonstrate that due to inlining order there
are cases where abstract variable DIEs are not constructed since the
abstract subprogram was built due to a previous inlining that optimized
away those variables. This produces incorrect debug info (the 'missing'
abstract variable causes the inlined instance of that variable to be
emitted with a full description (name, line, file) rather than
referencing the abstract origin), but this commit at least ensures that
it doesn't crash...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210143 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-04 01:30:59 +00:00
Rafael Espindola
2d21b25393 Allow alias to point to an arbitrary ConstantExpr.
This  patch changes GlobalAlias to point to an arbitrary ConstantExpr and it is
up to MC (or the system assembler) to decide if that expression is valid or not.

This reduces our ability to diagnose invalid uses and how early we can spot
them, but it also lets us do things like

@test5 = alias inttoptr(i32 sub (i32 ptrtoint (i32* @test2 to i32),
                                 i32 ptrtoint (i32* @bar to i32)) to i32*)

An important implication of this patch is that the notion of aliased global
doesn't exist any more. The alias has to encode the information needed to
access it in its metadata (linkage, visibility, type, etc).

Another consequence to notice is that getSection has to return a "const char *".
It could return a NullTerminatedStringRef if there was such a thing, but when
that was proposed the decision was to just uses "const char*" for that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210062 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-03 02:41:57 +00:00
David Blaikie
0d9056d766 DebugInfo: Assert that DbgVariables have associated DIEs
This was previously committed in r209680 and reverted in r209683 after
it caused sanitizer builds to crash.

The issue seems to be that the DebugLoc associated with dbg.value IR
intrinsics isn't necessarily accurate. Instead, we duplicate the
DIVariables and add an InlinedAt field to them to record their
location.

We were using this InlinedAt field to compute the LexicalScope for the
variable, but not using it in the abstract DbgVariable construction and
mapping. This resulted in a formal parameter to the current concrete
function, correctly having no InlinedAt information, but incorrectly
having a DebugLoc that described an inlined location within the
function... thus an abstract DbgVariable was created for the variable,
but its DIE was never constructed (since the LexicalScope had no such
variable). This DbgVariable was silently ignored (by testing for a
non-null DIE on the abstract DbgVariable).

So, fix this by using the right scoping information when constructing
abstract DbgVariables.

In the long run, I suspect we want to undo the work that added this
second kind of location tracking and fix the places where the DebugLoc
propagation on the dbg.value intrinsic fails. This will shrink debug
info (by not duplicating DIVariables), make it more efficient (by not
having to construct new DIVariable metadata nodes to try to map back to
a single variable), and benefit all instructions.

But perhaps there are insurmountable issues with DebugLoc quality that
I'm unaware of... I just don't know how we can't /just keep the DebugLoc
from the dbg.declare to the dbg.values and never get this wrong/.

Some history context:

http://llvm.org/viewvc/llvm-project?view=revision&revision=135629
http://llvm.org/viewvc/llvm-project?view=revision&revision=137253

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209984 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-01 03:38:13 +00:00