by reusing more of the existing machinery
This is a follow-up to r312169.
Thanks to Björn Pettersson for the testcase!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312773 91177308-0d34-0410-b5e6-96231b3b80d8
S_UDT records are basically the "bridge" between the debugger's
expression evaluator and the type information. If you type
(Foo*)nullptr into the watch window, the debugger looks for an
S_UDT record named Foo. If it can find one, it displays your type.
Otherwise you get an error.
We have always understood this to mean that if you have code like
this:
struct A {
int X;
};
struct B {
typedef A AT;
AT Member;
};
that you will get 3 S_UDT records. "A", "B", and "B::AT". Because
if you were to type (B::AT*)nullptr into the debugger, it would
need to find an S_UDT record named "B::AT".
But "B::AT" is actually the S_UDT record that would be generated
if B were a namespace, not a struct. So the debugger needs to be
able to distinguish this case. So what it does is:
1. Look for an S_UDT named "B::AT". If it finds one, it knows
that AT is in a namespace.
2. If it doesn't find one, split at the scope resolution operator,
and look for an S_UDT named B. If it finds one, look up the type
for B, and then look for AT as one of its members.
With this algorithm, S_UDT records for nested typedefs are not just
unnecessary, but actually wrong!
The results of implementing this in clang are dramatic. It cuts
our /DEBUG:FASTLINK PDB sizes by more than 50%, and we go from
being ~20% larger than MSVC PDBs on average, to ~40% smaller.
It also slightly speeds up link time. We get about 10% faster
links than without this patch.
Differential Revision: https://reviews.llvm.org/D37410
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312583 91177308-0d34-0410-b5e6-96231b3b80d8
Debug information can be, and was, corrupted when the runtime
remainder loop was fully unrolled. This is because a !null node can
be created instead of a unique one describing the loop. In this case,
the original node gets incorrectly updated with the NewLoopID
metadata.
In the case when the remainder loop is going to be quickly fully
unrolled, there isn't the need to add loop metadata for it anyway.
Differential Revision: https://reviews.llvm.org/D37338
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312471 91177308-0d34-0410-b5e6-96231b3b80d8
We have llvm-readobj for dumping CodeView from object files, and
llvm-pdbutil has always been more focused on PDB. However,
llvm-pdbutil has a lot of useful options for summarizing debug
information in aggregate and presenting high level statistical
views. Furthermore, it's arguably better as a testing tool since
we don't have to write tests to conform to a state-machine like
structure where you match multiple lines in succession, each
depending on a previous match. llvm-pdbutil dumps much more
concisely, so it's possible to use single-line matches in many
cases where as with readobj tests you have to use multi-line
matches with an implicit state machine.
Because of this, I'm adding object file support to llvm-pdbutil.
In fact, this mirrors the cvdump tool from Microsoft, which also
supports both object files and pdb files. In the future we could
perhaps rename this tool llvm-cvutil.
In the meantime, this allows us to deep dive into object files
the same way we already can with PDB files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312358 91177308-0d34-0410-b5e6-96231b3b80d8
Issues addressed since original review:
- Moved removal of dead instructions found by
LiveIntervals::shrinkToUses() outside of loop iterating over
instructions to avoid instructions being deleted while pointed to by
iterator.
- Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
- The pass no longer forwards COPYs to physical register uses, since
doing so can break code that implicitly relies on the physical
register number of the use.
- The pass no longer forwards COPYs to undef uses, since doing so
can break the machine verifier by creating LiveRanges that don't
end on a use (since the undef operand is not considered a use).
[MachineCopyPropagation] Extend pass to do COPY source forwarding
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312328 91177308-0d34-0410-b5e6-96231b3b80d8
This adds a new command line option, -udt-stats, which breaks
down the stats of S_UDT records. These are one of the biggest
contributors to the size of /DEBUG:FASTLINK PDBs, so they need
some additional tools to be able to analyze their usage. This
option will dig into each S_UDT record and determine what kind
of record it points to, and then break down the statistics by
the target type. The goal here is to identify how our object
files differ from MSVC object files in S_UDT records, so that
we can output fewer of them and reach size parity.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312276 91177308-0d34-0410-b5e6-96231b3b80d8
It caused PR34387: Assertion failed: (RegNo < NumRegs && "Attempting to access record for invalid register number!")
> Issues identified by buildbots addressed since original review:
> - Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
> - The pass no longer forwards COPYs to physical register uses, since
> doing so can break code that implicitly relies on the physical
> register number of the use.
> - The pass no longer forwards COPYs to undef uses, since doing so
> can break the machine verifier by creating LiveRanges that don't
> end on a use (since the undef operand is not considered a use).
>
> [MachineCopyPropagation] Extend pass to do COPY source forwarding
>
> This change extends MachineCopyPropagation to do COPY source forwarding.
>
> This change also extends the MachineCopyPropagation pass to be able to
> be run during register allocation, after physical registers have been
> assigned, but before the virtual registers have been re-written, which
> allows it to remove virtual register COPY LiveIntervals that become dead
> through the forwarding of all of their uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312178 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we would just describe the first register and then call it
quits. This patch emits fragment expressions for each register.
<rdar://problem/34075307>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312169 91177308-0d34-0410-b5e6-96231b3b80d8
Issues identified by buildbots addressed since original review:
- Fixed ARMLoadStoreOptimizer bug exposed by this change in r311907.
- The pass no longer forwards COPYs to physical register uses, since
doing so can break code that implicitly relies on the physical
register number of the use.
- The pass no longer forwards COPYs to undef uses, since doing so
can break the machine verifier by creating LiveRanges that don't
end on a use (since the undef operand is not considered a use).
[MachineCopyPropagation] Extend pass to do COPY source forwarding
This change extends MachineCopyPropagation to do COPY source forwarding.
This change also extends the MachineCopyPropagation pass to be able to
be run during register allocation, after physical registers have been
assigned, but before the virtual registers have been re-written, which
allows it to remove virtual register COPY LiveIntervals that become dead
through the forwarding of all of their uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312154 91177308-0d34-0410-b5e6-96231b3b80d8
This change simplifies code that has to deal with
DIGlobalVariableExpression and mirrors how we treat DIExpressions in
debug info intrinsics. Before this change there were two ways of
representing empty expressions on globals, a nullptr and an empty
!DIExpression().
If someone needs to upgrade out-of-tree testcases:
perl -pi -e 's/(!DIGlobalVariableExpression\(var: ![0-9]*)\)/\1, expr: !DIExpression())/g' <MYTEST.ll>
will catch 95%.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312144 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Based on Fred's patch here: https://reviews.llvm.org/D6771
I can't seem to commandeer the old review, so I'm creating a new one.
With that change the locations exrpessions are pretty printed inline in the
DIE tree. The output looks like this for debug_loc entries:
DW_AT_location [DW_FORM_data4] (0x00000000
0x0000000000000001 - 0x000000000000000b: DW_OP_consts +3
0x000000000000000b - 0x0000000000000012: DW_OP_consts +7
0x0000000000000012 - 0x000000000000001b: DW_OP_reg0 RAX, DW_OP_piece 0x4
0x000000000000001b - 0x0000000000000024: DW_OP_breg5 RDI+0)
And like this for debug_loc.dwo entries:
DW_AT_location [DW_FORM_sec_offset] (0x00000000
Addr idx 2 (w/ length 190): DW_OP_consts +0, DW_OP_stack_value
Addr idx 3 (w/ length 23): DW_OP_reg0 RAX, DW_OP_piece 0x4)
Simple locations without ranges are printed inline:
DW_AT_location [DW_FORM_block1] (DW_OP_reg4 RSI, DW_OP_piece 0x4, DW_OP_bit_piece 0x20 0x0)
The debug_loc(.dwo) dumping in changed accordingly to factor the code.
Reviewers: dblaikie, aprantl, friss
Subscribers: mgorny, javed.absar, hiraditya, llvm-commits, JDevlieghere
Differential Revision: https://reviews.llvm.org/D37123
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312042 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.
This fixes PR34261.
The reland adds two extra checks to the original: It checks if the
DbgVariableLocation is valid before checking any of its fields, and
it only emits ranges with nonzero registers.
Reviewers: aprantl, rnk, zturner
Reviewed By: rnk
Subscribers: mgorny, llvm-commits, aprantl, hiraditya
Differential Revision: https://reviews.llvm.org/D36907
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312034 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Some variables show up in Visual Studio as "optimized out" even in -O0
-Od builds. This change fixes two issues that would cause this to
happen. The first issue is that not all DIExpressions we generate were
recognized by the CodeView writer. This has been addressed by adding
support for DW_OP_constu, DW_OP_minus, and DW_OP_plus. The second
issue is that we had no way to encode DW_OP_deref in CodeView. We get
around that by changinge the type we encode in the debug info to be
a reference to the type in the source code.
This fixes PR34261.
Reviewers: aprantl, rnk, zturner
Reviewed By: rnk
Subscribers: mgorny, llvm-commits, aprantl, hiraditya
Differential Revision: https://reviews.llvm.org/D36907
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311957 91177308-0d34-0410-b5e6-96231b3b80d8
S_UDT symbols are the debugger's "index" for all the structs,
typedefs, classes, and enums in a program. If any of those
structs/classes don't have a complete declaration, or if there
is a typedef to something that doesn't have a complete definition,
then emitting the S_UDT is unhelpful because it doesn't give
the debugger enough information to do anything useful. On the
other hand, it results in a huge size blow-up in the resulting
PDB, which is exacerbated by an order of magnitude when linking
with /DEBUG:FASTLINK.
With this patch, we drop S_UDT records for types that refer either
directly or indirectly (e.g. through a typedef, pointer, etc) to
a class/struct/union/enum without a complete definition. This
brings us about 50% of the way towards parity with /DEBUG:FASTLINK
PDBs generated from cl-compiled object files.
Differential Revision: https://reviews.llvm.org/D37162
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311904 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Most DIExpressions are empty or very simple. When they are complex, they
tend to be unique, so checking them inline is reasonable.
This also avoids the need for CodeGen passes to append to the
llvm.dbg.mir named md node.
See also PR22780, for making DIExpression not be an MDNode.
Reviewers: aprantl, dexonsmith, dblaikie
Subscribers: qcolombet, javed.absar, eraman, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D37075
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311594 91177308-0d34-0410-b5e6-96231b3b80d8
This adds support for dumping a summary of module symbols
and CodeView debug chunks. This option prints a table for
each module of all of the symbols that occurred in the module
and the number of times it occurred and total byte size. Then
at the end it prints the totals for the entire file.
Additionally, this patch adds the -jmc (just my code) option,
which suppresses modules which are from external libraries or
linker imports, so that you can focus only on the object files
and libraries that originate from your own source code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311338 91177308-0d34-0410-b5e6-96231b3b80d8
Re-committing after r311325 fixed an unintentional use of '#' comments in
clang.
The '#' token is not a comment for all targets (on ARM and AArch64 it marks an
immediate operand), so we shouldn't treat it as such.
Comments are already converted to AsmToken::EndOfStatement by
AsmLexer::LexLineComment, so this check was unnecessary.
Differential Revision: https://reviews.llvm.org/D36405
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widely used processors.
This occured to me when I saw that we were generating 'inc' and 'dec'
when for Haswell and newer we shouldn't. However, there were a few "X is
slow" things that we should probably just set.
I've avoided any of the "X is fast" features because most of those would
be pretty serious regressions on processors where X isn't actually fast.
The slow things are likely to be negligible costs on processors where
these aren't slow and a significant win when they are slow.
In retrospect this seems somewhat obvious. Not sure why we didn't do
this a long time ago.
Differential Revision: https://reviews.llvm.org/D36947
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311318 91177308-0d34-0410-b5e6-96231b3b80d8
Debug information for TLS variables on MIPS might have R_MIPS_TLS_DTPREL32
or R_MIPS_TLS_DTPREL64 relocations. This patch adds a support for such
relocations in the `RelocVisitor`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311031 91177308-0d34-0410-b5e6-96231b3b80d8
The %T lit expansion expands to a common directory shared between all the tests in the same directory, which is unexpected and unintuitive, and more importantly, it's been a source of subtle race conditions and flaky tests. In https://reviews.llvm.org/D35396, it was agreed that it would be best to simply ban %T and only keep %t, which is unique to each test. When a test needs a temporary directory, it can just create one using mkdir %t.
This patch removes %T in llvm.
Differential Revision: https://reviews.llvm.org/D36495
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310953 91177308-0d34-0410-b5e6-96231b3b80d8
These were pending in a separate patch but I forgot to squash them
before comitting, and this one didn't go through.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310764 91177308-0d34-0410-b5e6-96231b3b80d8
The '#' token is not a comment for all targets (on ARM and AArch64 it marks an
immediate operand), so we shouldn't treat it as such.
Comments are already converted to AsmToken::EndOfStatement by
AsmLexer::LexLineComment, so this check was unnecessary.
Differential Revision: https://reviews.llvm.org/D36405
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310457 91177308-0d34-0410-b5e6-96231b3b80d8
For some reason I didn't see this failure the first time. The
output format changed slightly, so we just have to update the
test for the new format.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310442 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we limited ourselves to only emitting nested classes, but we
need other kinds of types as well.
This fixes the Visual Studio STL visualizers, so that users can
visualize std::string and other objects.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310410 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
MIRParserImpl::computeFunctionProperties uses MRI.getNumVirtRegs() to
set the NoVReg property. By adding a bunch of registers to the MIR test
cases, the NoVReg property is not set when importing the MIR. Otherwise
NoVReg is set after instruction selection while the machine instructions
still contain virtual registers, causing expensive checks to fail.
Reviewers: efriedma, MatzeB, aprantl
Reviewed By: MatzeB, aprantl
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D36152
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310178 91177308-0d34-0410-b5e6-96231b3b80d8
This extends the native reader to enable llvm-pdbutil to list the enums in a
PDB and it includes a simple test. It does not yet list the values in the
enumerations, which requires an actual implementation of
NativeEnumSymbol::FindChildren.
To exercise this code, use a command like:
llvm-pdbutil pretty -native -enums foo.pdb
Differential Revision: https://reviews.llvm.org/D35738
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310144 91177308-0d34-0410-b5e6-96231b3b80d8
