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
When ‘#pragma clang loop vectorize(assume_safety)’ was specified on a loop other loop hints were lost. The problem is that CGLoopInfo attaches metadata differently than EmitCondBrHints in CGStmt. For do-loops CGLoopInfo attaches metadata to the br in the body block and for while and for loops, the inc block. EmitCondBrHints on the other hand always attaches data to the br in the cond block. When specifying assume_safety CGLoopInfo emits an empty llvm.loop metadata shadowing the metadata in the cond block. Loop transformations like rotate and unswitch would then eliminate the cond block and its non-empty metadata.
This patch unifies both approaches for adding metadata and modifies the existing safety tests to include non-assume_safety loop hints.
llvm-svn: 243315
Some const-correctness changes snuck in here too, since they were in the
area of code I was modifying.
This seems to make Clang actually work without Bus Error on
32bit-sparc.
Follow-up patches will factor out a trailing-object helper class, to
make classes using the idiom of appending objects to other objects
easier to understand, and to ensure (with static_assert) that required
alignment guarantees continue to hold.
Differential Revision: http://reviews.llvm.org/D10272
llvm-svn: 242554
Previously, clang/llvm treated inline-asm instructions conservatively,
choosing not to eliminate the instructions or hoisting them out of a loop
even when it was safe to do so. This commit makes changes to attach a
readonly or readnone attribute to an inline-asm instruction, which enables
passes such as LICM and EarlyCSE to move or optimize away the instruction.
rdar://problem/11358192
Differential Revision: http://reviews.llvm.org/D10546
llvm-svn: 241930
Added parsing, sema analysis and codegen for '#pragma omp taskgroup' directive (OpenMP 4.0).
The code for directive is generated the following way:
#pragma omp taskgroup
<body>
void __kmpc_taskgroup(<loc>, thread_id);
<body>
void __kmpc_end_taskgroup(<loc>, thread_id);
llvm-svn: 240011
Instead, just EvaluateAsInt().
Follow-up to r239549: rsmith points out that isICE() is expensive;
seems like it's not the right concept anyway, as it fails on
`static const' in C, and will actually trigger the assert below on:
test/Sema/inline-asm-validate-x86.c
llvm-svn: 239651
Specifying #pragma clang loop vectorize(assume_safety) on a loop adds the
mem.parallel_loop_access metadata to each load/store operation in the loop. This
metadata tells loop access analysis (LAA) to skip memory dependency checking.
llvm-svn: 239572
For inline assembly immediate constraints, we currently always use
EmitScalarExpr, instead of directly emitting the constant. When the
overflow sanitizer is enabled, this generates overflow intrinsics
instead of constants.
Instead, emit a constant for constraints that either require an
immediate (e.g. 'I' on X86), or only accepts constants (immediate
or symbolic; i.e., don't accept registers or memory).
Fixes PR19763.
Differential Revision: http://reviews.llvm.org/D10255
llvm-svn: 239549
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
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
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
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
Patch adds proper generation of debug info for all OpenMP regions. Also, all OpenMP regions are generated in a termination scope, because standard does not allow to throw exceptions out of structured blocks, associated with the OpenMP regions
Differential Revision: http://reviews.llvm.org/D7935
llvm-svn: 231757
This reverts commit r231752.
It was failing to link with cmake:
lib64/libclangCodeGen.a(CGOpenMPRuntime.cpp.o):/home/espindola/llvm/llvm/tools/clang/lib/CodeGen/CGOpenMPRuntime.cpp:function clang::CodeGen::InlinedOpenMPRegionRAII::~InlinedOpenMPRegionRAII(): error: undefined reference to 'clang::CodeGen::EHScopeStack::popTerminate()'
clang-3.7: error: linker command failed with exit code 1 (use -v to see invocation)
llvm-svn: 231754
Patch adds proper generation of debug info for all OpenMP regions. Also, all OpenMP regions are generated in a termination scope, because standard does not allow to throw exceptions out of structured blocks, associated with the OpenMP regions
Differential Revision: http://reviews.llvm.org/D7935
llvm-svn: 231752
modifiers on them. If we have a matching output constraint with
an early clobber make sure we don't propagate that to the input
constraint.
llvm-svn: 228422
Summary:
Named registers with the constraint "=&r" currently lose the early clobber flag
and turn into "=r" when converted to LLVM-IR. This patch correctly passes it on.
Reviewers: atanasyan
Reviewed By: atanasyan
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D7346
llvm-svn: 228143
distinction between the different use-cases. With the previous default
behavior we would occasionally emit empty debug locations in situations
where they actually were strictly required (= on invoke insns).
We now have a choice between defaulting to an empty location or an
artificial location.
Specifically, this fixes a bug caused by a missing debug location when
emitting C++ EH cleanup blocks from within an artificial function, such as
an ObjC destroy helper function.
rdar://problem/19670595
llvm-svn: 228003
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
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
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
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
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
The logic for lowering profiling counters has been moved to an LLVM
pass. Emit the intrinsics rather than duplicating the whole pass in
clang.
llvm-svn: 223683
An updated implemnentation of VLA types capturing based on previously committed solution for Lambdas.
This version captures the whole VLA type instead of particular variables which are part of VLA size expression and allows to use previusly calculated size of VLA type in captured regions. Required for OpenMP.
Differential Revision: http://reviews.llvm.org/D5099
llvm-svn: 220850
Previously loop hints such as #pragma loop vectorize_width(#) required a constant. This patch allows a constant expression to be used as well. Such as a non-type template parameter or an expression (2 * c + 1).
Reviewed by Richard Smith
llvm-svn: 219589
Includes parsing and semantic analysis for 'omp teams' directive support from OpenMP 4.0. Adds additional analysis to 'omp target' directive with 'omp teams' directive.
llvm-svn: 219385
Includes parsing and semantic analysis for 'omp teams' directive support from OpenMP 4.0. Adds additional analysis to 'omp target' directive with 'omp teams' directive.
llvm-svn: 219197
If control falls off the end of a function after an __asm block, MSVC
assumes that the inline assembly filled the EAX and possibly EDX
registers with an appropriate return value. This functionality is used
in inline functions returning 64-bit integers in system headers, so we
need some amount of compatibility.
This is implemented in Clang by adding extra output constraints to every
inline asm block, and storing the resulting output registers into the
return value slot. If we see an asm block somewhere in the function
body, we emit a normal epilogue instead of marking the end of the
function with a return type unreachable.
Normal returns in functions not using this functionality will overwrite
the return value slot, and in most cases LLVM should be able to
eliminate the dead stores.
Fixes PR17201.
Reviewed By: majnemer
Differential Revision: http://reviews.llvm.org/D5177
llvm-svn: 217187
