CodeViewDebug sets Asm to nullptr to disable debug info generation. You
can get a .ll file like no-cus.ll from 'clang -gcodeview -g0', which
happens in the ubsan test suite.
llvm-svn: 302923
Turns out that the Fission/Split DWARF package format (DWP) is currently
insufficient to handle cross-CU (ref_addr) references. So for now,
duplicate any debug info needed in these situations:
* inlined_subroutine's abstract_origin
* inlined variable's abstract_origin
* types
Keep the ref_addr behavior in general, including in the split DWARF
inline debug info that can be emitted into the object files for online
symbolication.
Keep a flag to use the old (ref_addr) behavior for testing ways of
addressing this limitation in the DWP tool (& for those not using DWP
packaging).
llvm-svn: 302858
Fixes inalloca parameters, which previously all pointed to the same
offset. Extend the test to use llvm-readobj so that we can test the
offset in a readable way.
llvm-svn: 302578
Most of the time we know exactly how many type records we
have in a list, and we want to use the visitor to deserialize
them into actual records in a database. Previously we were
just using push_back() every time without reserving the space
up front in the vector. This is obviously terrible from a
performance standpoint, and it's not uncommon to have PDB
files with half a million type records, where the performance
degredation was quite noticeable.
llvm-svn: 302302
This makes it simpler for the runtime to consistently handle the entries
in the function sled index in both 32 and 64 bit platforms where the
XRay runtime works.
Follow-up on D32693.
llvm-svn: 302111
Summary:
This change adds a new section to the xray-instrumented binary that
stores an index into ranges of the instrumentation map, where sleds
associated with the same function can be accessed as an array. At
runtime, we can get access to this index by function ID offset allowing
for selective patching and unpatching by function ID.
Each entry in this new section (xray_fn_idx) will include two pointers
indicating the start and one past the end of the sleds associated with
the same function. These entries will be 16 bytes long on x86 and
aarch64. On arm, we align to 16 bytes anyway so the runtime has to take
that into consideration.
__{start,stop}_xray_fn_idx will be the symbols that the runtime will
look for when we implement the selective patching/unpatching by function
id APIs. Because XRay synthesizes the function id's in a monotonically
increasing manner at runtime now, implementations (and users) can use
this table to look up the sleds associated with a specific function.
This is useful in implementations that want to do things like:
- Implement coverage mode for functions by patching everything
pre-main, then as functions are encountered, the installed handler
can unpatch the function that's been encountered after recording
that it's been called.
- Do "learning mode", so that the implementation can figure out some
statistical information about function calls by function id for a
time being, and then determine which functions are worth
uninstrumenting at runtime.
- Do "selective instrumentation" where an implementation can
specifically instrument only certain function id's at runtime
(either based on some external data, or through some other
heuristics) instead of patching all the instrumented functions at
runtime.
Reviewers: dblaikie, echristo, chandlerc, javed.absar
Subscribers: pelikan, aemerson, kpw, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D32693
llvm-svn: 302109
Compiler emitted synthetic types may not have an associated DIFile
(translation unit). In such a case, when generating CodeView debug type
information, we would attempt to compute an absolute filepath which
would result in a segfault due to a NULL DIFile*. If there is no source
file associated with the type, elide the type index entry for the type
and record the type information. This actually results in higher
fidelity debug information than clang/C2 as of this writing.
Resolves PR32668!
llvm-svn: 302085
Previously we wrote line information and file checksum
information, but we did not write information about inlinee
lines and functions. This patch adds support for that.
llvm-svn: 301936
Fixes the issue highlighted in
http://lists.llvm.org/pipermail/cfe-dev/2014-June/037500.html.
The DW_AT_decl_file and DW_AT_decl_line attributes on namespaces can
prevent LLVM from uniquing types that are in the same namespace. They
also don't carry any meaningful information.
rdar://problem/17484998
Differential Revision: https://reviews.llvm.org/D32648
llvm-svn: 301706
We have a lot of very similarly named classes related to
dealing with module debug info. This patch has NFC, it just
renames some classes to be more descriptive (albeit slightly
more to type). The mapping from old to new class names is as
follows:
Old | New
ModInfo | DbiModuleDescriptor
ModuleSubstream | ModuleDebugFragment
ModStream | ModuleDebugStream
With the corresponding Builder classes renamed accordingly.
Differential Revision: https://reviews.llvm.org/D32506
llvm-svn: 301555
DISubprogram currently has 10 pointer operands, several of which are
often nullptr. This patch reduces the amount of memory allocated by
DISubprogram by rearranging the operands such that containing type,
template params, and thrown types come last, and are only allocated
when they are non-null (or followed by non-null operands).
This patch also eliminates the entirely unused DisplayName operand.
This saves up to 4 pointer operands per DISubprogram. (I tried
measuring the effect on peak memory usage on an LTO link of an X86
llc, but the results were very noisy).
This reapplies r301498 with an attempted workaround for g++.
Differential Revision: https://reviews.llvm.org/D32560
llvm-svn: 301501
DISubprogram currently has 10 pointer operands, several of which are
often nullptr. This patch reduces the amount of memory allocated by
DISubprogram by rearranging the operands such that containing type,
template params, and thrown types come last, and are only allocated
when they are non-null (or followed by non-null operands).
This patch also eliminates the entirely unused DisplayName operand.
This saves up to 4 pointer operands per DISubprogram. (I tried
measuring the effect on peak memory usage on an LTO link of an X86
llc, but the results were very noisy).
llvm-svn: 301498
For Swift we would like to be able to encode the error types that a
function may throw, so the debugger can display them alongside the
function's return value when finish-ing a function.
DWARF defines DW_TAG_thrown_type (intended to be used for C++ throw()
declarations) that is a perfect fit for this purpose. This patch wires
up support for DW_TAG_thrown_type in LLVM by adding a list of thrown
types to DISubprogram.
To offset the cost of the extra pointer, there is a follow-up patch
that turns DISubprogram into a variable-length node.
rdar://problem/29481673
Differential Revision: https://reviews.llvm.org/D32559
llvm-svn: 301489
Summary: No test case since I'm not aware of an in-tree target that needs this.
Reviewers: hans
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32398
llvm-svn: 301311
1. RegisterClass::getSize() is split into two functions:
- TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
- TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
- TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;
This will allow making those values depend on subtarget features in the
future.
Differential Revision: https://reviews.llvm.org/D31783
llvm-svn: 301221
When functions are terminated by unreachable instructions, the last
instruction might trigger a CFI instruction to be generated. However,
emitting it would be be illegal since the function (and thus the FDE
the CFI is in) has already ended with the previous instruction.
Darwin's dwarfdump --verify --eh-frame complains about this and the
specification supports this.
Relevant bits from the DWARF 5 standard (6.4 Call Frame Information):
"[The] address_range [field in an FDE]: The number of bytes of
program instructions described by this entry."
"Row creation instructions: [...]
The new location value is always greater than the current one."
The first quotation implies that a CFI cannot describe a target
address outside of the enclosing FDE's range.
rdar://problem/26244988
Differential Revision: https://reviews.llvm.org/D32246
llvm-svn: 301219
In dwo files the fixed offset can be used - if the dwos are linked into
a dwp, the dwo consumer must use the dwp tables to find out where the
original range of the debug_info was and resolve the "section relative"
value relative to that original range - effectively
avoiding/reimplementing the relocation handling.
llvm-svn: 301072
Since Split DWARF needs to name the actual .dwo file that is generated,
it can't be known at the time the llvm::Module is produced as it may be
merged with other Modules before the object is generated and that object
may be generated with any name.
By passing the Split DWARF file name when LLVM is producing object code
the .dwo file name in the object file can match correctly.
The support for Split DWARF for implicit modules remains the same -
using metadata to store the dwo name and dwo id so that potentially
multiple skeleton CUs referring to different dwo files can be generated
from one llvm::Module.
llvm-svn: 301062
In addition to the original commit, tighten the condition for when to
pad empty functions to COFF Windows. This avoids running into problems
when targeting e.g. Win32 AMDGPU, which caused test failures when this
was committed initially.
llvm-svn: 301047
Empty functions can lead to duplicate entries in the Guard CF Function
Table of a binary due to multiple functions sharing the same RVA,
causing the kernel to refuse to load that binary.
We had a terrific bug due to this in Chromium.
It turns out we were already doing this for Mach-O in certain
situations. This patch expands the code for that in
AsmPrinter::EmitFunctionBody() and renames
TargetInstrInfo::getNoopForMachoTarget() to simply getNoop() since it
seems it was used for not just Mach-O anyway.
Differential Revision: https://reviews.llvm.org/D32330
llvm-svn: 301040
Associate the version-when-defined with definitions of standard DWARF
constants. Identify the "vendor" for DWARF extensions.
Use this information to verify FORMs in .debug_abbrev are defined as
of the DWARF version specified in the associated unit.
Removed two tests that had specified DWARF v1 (which essentially does
not exist).
Differential Revision: http://reviews.llvm.org/D30785
llvm-svn: 300875
- introduced in r300522 and found via the Swift LLDB testsuite.
The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.
rdar://problem/31707602
llvm-svn: 300793
- introduced in r300522 and found via the Swift LLDB testsuite.
The fix is to set the location kind to memory whenever an FrameIndex
location is emitted.
rdar://problem/31707602
llvm-svn: 300790
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.
This adds an lshrInPlace(const APInt &) version as well.
Differential Revision: https://reviews.llvm.org/D32155
llvm-svn: 300566
The DWARF specification knows 3 kinds of non-empty simple location
descriptions:
1. Register location descriptions
- describe a variable in a register
- consist of only a DW_OP_reg
2. Memory location descriptions
- describe the address of a variable
3. Implicit location descriptions
- describe the value of a variable
- end with DW_OP_stack_value & friends
The existing DwarfExpression code is pretty much ignorant of these
restrictions. This used to not matter because we only emitted very
short expressions that we happened to get right by accident. This
patch makes DwarfExpression aware of the rules defined by the DWARF
standard and now chooses the right kind of location description for
each expression being emitted.
This would have been an NFC commit (for the existing testsuite) if not
for the way that clang describes captured block variables. Based on
how the previous code in LLVM emitted locations, DW_OP_deref
operations that should have come at the end of the expression are put
at its beginning. Fixing this means changing the semantics of
DIExpression, so this patch bumps the version number of DIExpression
and implements a bitcode upgrade.
There are two major changes in this patch:
I had to fix the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.
When lowering a DBG_VALUE, the decision of whether to emit a register
location description or a memory location description depends on the
MachineLocation — register machine locations may get promoted to
memory locations based on their DIExpression. (Future) optimization
passes that want to salvage implicit debug location for variables may
do so by appending a DW_OP_stack_value. For example:
DBG_VALUE, [RBP-8] --> DW_OP_fbreg -8
DBG_VALUE, RAX --> DW_OP_reg0 +0
DBG_VALUE, RAX, DIExpression(DW_OP_deref) --> DW_OP_reg0 +0
All testcases that were modified were regenerated from clang. I also
added source-based testcases for each of these to the debuginfo-tests
repository over the last week to make sure that no synchronized bugs
slip in. The debuginfo-tests compile from source and run the debugger.
https://bugs.llvm.org/show_bug.cgi?id=32382
<rdar://problem/31205000>
Differential Revision: https://reviews.llvm.org/D31439
llvm-svn: 300522
If we have an array of a user-defined aggregates for which there was an
ODR violation, then the array size will not necessarily match the number
of elements times the size of the element.
Fixes PR32383
llvm-svn: 298750
It is not guaranteed that the memory used for MachineBasicBlocks in
the previous MachineFunction hasn't been freed, so holding on to a
pointer to the last function's isn't correct. Particularly I have
observed the sret.ll testcase failing because the first BasicBlock in
the new function happened to be allocated to the exact same memory as
the previously saved and (deleted) PrevInstBB.
llvm-svn: 298642
Also add an assertion for the case that there are multiple FI
expressions with a DW_OP_LLVM_fragment; which should violate internal
constraints in DbgVariable.
llvm-svn: 298518
If a register location can only be described by a complex expression
(i.e., multiple subregisters) it doesn't safely compose with another
complex expression. For example, it is not possible to apply a
DW_OP_deref operation to multiple DW_OP_pieces.
llvm-svn: 298472
until the rest of the expression is known.
This is still an NFC refactoring in preparation of a subsequent bugfix.
This reapplies r298388 with a bugfix for non-physical frame registers.
llvm-svn: 298471
If a register location can only be described by a complex expression
(i.e., multiple subregisters) it doesn't safely compose with another
complex expression. For example, it is not possible to apply a
DW_OP_deref operation to multiple DW_OP_pieces.
llvm-svn: 298389
