Commit Graph

219 Commits

Author SHA1 Message Date
Daniel Sanders 9f3cf55e63 [mir] Serialize DILocation inline when not possible to use a metadata reference
Summary:
Sometimes MIR-level passes create DILocations that were not present in the
LLVM-IR. For example, it may merge two DILocations together to produce a
DILocation that points to line 0.

Previously, the address of these DILocations were printed which prevented the
MIR from being read back into LLVM. With this patch, DILocations will use
metadata references where possible and fall back on serializing them inline like so:
    MOV32mr %stack.0.x.addr, 1, _, 0, _, %0, debug-location !DILocation(line: 1, scope: !15)

Reviewers: aprantl, vsk, arphaman

Reviewed By: aprantl

Subscribers: probinson, llvm-commits

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D55243

llvm-svn: 349035
2018-12-13 14:25:27 +00:00
Hsiangkai Wang 957578ddf7 [CodeGen] Fix bugs in BranchFolderPass when debug labels are generated.
Skip DBG_VALUE and DBG_LABEL in branch folding algorithms.

The bug is reported in
https://bugs.chromium.org/p/chromium/issues/detail?id=898160.

Differential Revision: https://reviews.llvm.org/D54199

llvm-svn: 347964
2018-11-30 08:07:29 +00:00
Daniel Sanders 162da63e05 Add 'REQUIRES: default_triple' to test/CodeGen/MIR/X86/zero-probability.mir
llvm-svn: 346368
2018-11-07 23:33:55 +00:00
Reid Kleckner 2bcb288ade [codeview] Let the X86 backend tell us the VFRAME offset adjustment
Use MachineFrameInfo's OffsetAdjustment field to pass this information
from the target to CodeViewDebug.cpp. The X86 backend doesn't use it for
any other purpose.

This fixes PR38857 in the case where there is a non-aligned quantity of
CSRs and a non-aligned quantity of locals.

llvm-svn: 346062
2018-11-03 00:41:52 +00:00
Matthias Braun a83403892a MachineOperand/MIParser: Do not print debug-use flag, infer it
The debug-use flag must be set exactly for uses on DBG_VALUEs.  This is
so obvious that it can be trivially inferred while parsing. This will
reduce noise when printing while omitting an information that has little
value to the user.

The parser will keep recognizing the flag for compatibility with old
`.mir` files.

Differential Revision: https://reviews.llvm.org/D53903

llvm-svn: 345671
2018-10-30 23:28:27 +00:00
Francis Visoiu Mistrih 9a9f16ba87 [MIR] Simplify and move MIR test
Also fixes a Machine Verifier issue.

llvm-svn: 345396
2018-10-26 16:00:29 +00:00
Reid Kleckner 9ea2c01264 [codeview] Emit S_FRAMEPROC and use S_DEFRANGE_FRAMEPOINTER_REL
Summary:
Before this change, LLVM would always describe locals on the stack as
being relative to some specific register, RSP, ESP, EBP, ESI, etc.
Variables in stack memory are pretty common, so there is a special
S_DEFRANGE_FRAMEPOINTER_REL symbol for them. This change uses it to
reduce the size of our debug info.

On top of the size savings, there are cases on 32-bit x86 where local
variables are addressed from ESP, but ESP changes across the function.
Unlike in DWARF, there is no FPO data to describe the stack adjustments
made to push arguments onto the stack and pop them off after the call,
which makes it hard for the debugger to find the local variables in
frames further up the stack.

To handle this, CodeView has a special VFRAME register, which
corresponds to the $T0 variable set by our FPO data in 32-bit.  Offsets
to local variables are instead relative to this value.

This is part of PR38857.

Reviewers: hans, zturner, javed.absar

Subscribers: aprantl, hiraditya, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D52217

llvm-svn: 343543
2018-10-01 21:59:45 +00:00
Matthias Braun 7159daa68e MIRParser: Check that instructions only reference DILocation metadata
llvm-svn: 343505
2018-10-01 17:50:52 +00:00
Carlos Alberto Enciso 81d8ef2196 [DebugInfo][Dexter] Incorrect DBG_VALUE after MCP dead copy instruction removal.
When MachineCopyPropagation eliminates a dead 'copy', its associated debug information becomes invalid. as the recorded register has been removed.  It causes the debugger to display wrong variable value.

Differential Revision: https://reviews.llvm.org/D52614

llvm-svn: 343445
2018-10-01 08:14:44 +00:00
Michael Berg c72a7259be add IR flags to MI
Summary: Initial support for nsw, nuw and exact flags in MI

Reviewers: spatel, hfinkel, wristow

Reviewed By: spatel

Subscribers: nlopes

Differential Revision: https://reviews.llvm.org/D51738

llvm-svn: 341996
2018-09-11 21:35:32 +00:00
Michael Berg 1b34b01a8e [NFC] - in preparation for adding nsw, nuw and exact as flags to MI
llvm-svn: 341565
2018-09-06 17:07:29 +00:00
Krzysztof Parzyszek cc3f630252 Consistently use MemoryLocation::UnknownSize to indicate unknown access size
1. Change the software pipeliner to use unknown size instead of dropping
   memory operands. It used to do it before, but MachineInstr::mayAlias
   did not handle it correctly.
2. Recognize UnknownSize in MachineInstr::mayAlias.
3. Print and parse UnknownSize in MIR.

Differential Revision: https://reviews.llvm.org/D50339

llvm-svn: 340208
2018-08-20 20:37:57 +00:00
Chandler Carruth 75ca6be1c1 [x86/MIR] Implement support for pre- and post-instruction symbols, as
well as MIR parsing support for `MCSymbol` `MachineOperand`s.

The only real way to test pre- and post-instruction symbol support is to
use them in operands, so I ended up implementing that within the patch
as well. I can split out the operand support if folks really want but it
doesn't really seem worth it.

The functional implementation of pre- and post-instruction symbols is
now *completely trivial*. Two tiny bits of code in the (misnamed)
AsmPrinter. It should be completely target independent as well. We emit
these exactly the same way as we emit basic block labels. Most of the
code here is to give full dumping, MIR printing, and MIR parsing support
so that we can write useful tests.

The MIR parsing of MC symbol operands still isn't 100%, as it forces the
symbols to be non-temporary and non-local symbols with names. However,
those names often can encode most (if not all) of the special semantics
desired, and unnamed symbols seem especially annoying to serialize and
de-serialize. While this isn't perfect or full support, it seems plenty
to write tests that exercise usage of these kinds of operands.

The MIR support for pre-and post-instruction symbols was quite
straightforward. I chose to print them out in an as-if-operand syntax
similar to debug locations as this seemed the cleanest way and let me
use nice introducer tokens rather than inventing more magic punctuation
like we use for memoperands.

However, supporting MIR-based parsing of these symbols caused me to
change the design of the symbol support to allow setting arbitrary
symbols. Without this, I don't see any reasonable way to test things
with MIR.

Differential Revision: https://reviews.llvm.org/D50833

llvm-svn: 339962
2018-08-16 23:11:05 +00:00
Francis Visoiu Mistrih 8b2ab91a5d [DebugInfo][X86] Add start-after flags to MIR tests
These tests would fail with -verify-machineinstrs because the MI
generated from the IR would be merged with the one already in the MIR
files, and we get the following error:

```
*** Bad machine code: Function has NoVRegs property but there are VReg operands ***
- function:    f
```

Differential Revision: https://reviews.llvm.org/D49191

llvm-svn: 336907
2018-07-12 14:36:48 +00:00
Mikael Holmen 42f7bc96dd [DebugInfo] Make sure all DBG_VALUEs' reguse operands have IsDebug property
Summary:
In some cases, these operands lacked the IsDebug property, which is meant to signal that
they should not affect codegen. This patch adds a check for this property in the
MachineVerifier and adds it where it was missing.

This includes refactorings to use MachineInstrBuilder construction functions instead of
manually setting up the intrinsic everywhere.

Patch by: JesperAntonsson

Reviewers: aprantl, rnk, echristo, javed.absar

Reviewed By: aprantl

Subscribers: qcolombet, sdardis, nemanjai, JDevlieghere, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D48319

llvm-svn: 335214
2018-06-21 10:03:34 +00:00
Matt Davis a245c765a8 [MIRParser] Update a diagnostic message to use the correct register sigil. NFC
Summary:
Patch r323922 changed the sigil for physical registers to '$',  instead of '%'.
An error message was missed during this change, and reports the wrong sigil.
This patch corrects that diagnostic and the tests that check that error string.


Reviewers: zer0, bjope

Reviewed By: bjope

Subscribers: bjope, thegameg, plotfi, llvm-commits

Differential Revision: https://reviews.llvm.org/D48086

llvm-svn: 335066
2018-06-19 18:39:40 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Michael Berg 7d1b25d053 MachineInst support mapping SDNode fast math flags for support in Back End code generation
Summary:
Machine Instruction flags for fast math support and MIR print support


Reviewers: spatel, arsenm

Reviewed By: arsenm

Subscribers: wdng

Differential Revision: https://reviews.llvm.org/D45781

llvm-svn: 331417
2018-05-03 00:07:56 +00:00
Francis Visoiu Mistrih 57fcd3454a [MIR] Add support for debug metadata for fixed stack objects
Debug var, expr and loc were only supported for non-fixed stack objects.

This patch adds the following fields to the "fixedStack:" entries, and
renames the ones from "stack:" to:

* debug-info-variable
* debug-info-expression
* debug-info-location

Differential Revision: https://reviews.llvm.org/D46032

llvm-svn: 330859
2018-04-25 18:58:06 +00:00
Francis Visoiu Mistrih 3abf05739f [MIR] Allow frame-setup and frame-destroy on the same instruction
Nothing prevents us from having both frame-setup and frame-destroy on
the same instruction.

When merging:
* frame-setup OPCODE1
* frame-destroy OPCODE2
into
* frame-setup frame-destroy OPCODE3

we want to be able to print and parse both flags.

llvm-svn: 327442
2018-03-13 19:53:16 +00:00
Puyan Lotfi 43e94b15ea Followup on Proposal to move MIR physical register namespace to '$' sigil.
Discussed here:

http://lists.llvm.org/pipermail/llvm-dev/2018-January/120320.html

In preparation for adding support for named vregs we are changing the sigil for
physical registers in MIR to '$' from '%'. This will prevent name clashes of
named physical register with named vregs.

llvm-svn: 323922
2018-01-31 22:04:26 +00:00
Justin Bogner 6e36f8250c Add triples or specify REQUIRES: default_triple to some tests
These were all failing when building the X86 backend but specifying
LLVM_DEFAULT_TARGET_TRIPLE=''.

llvm-svn: 323608
2018-01-27 23:31:09 +00:00
Alexander Ivchenko 347921a281 [x86] Mostly reautogenerate a bunch of tests that affect D37775. NFC
Tests required minor manual tweaks:
CodeGen/MIR/X86/generic-instr-type.mir
CodeGen/X86/GlobalISel/select-copy.mir
CodeGen/X86/GlobalISel/select-ext.mir
CodeGen/X86/GlobalISel/select-intrinsic-x86-flags-read-u32.mir
CodeGen/X86/GlobalISel/select-phi.mir
CodeGen/X86/GlobalISel/select-trunc.mir
CodeGen/X86/GlobalISel/select-frameIndex.mir

And following tests are split into 32/64 versions:
CodeGen/X86/GlobalISel/legalize-GV.mir
CodeGen/X86/GlobalISel/select-frameIndex.mir

llvm-svn: 323209
2018-01-23 15:48:50 +00:00
Matthias Braun 8bb5228db9 Move tests to the correct place
test/CodeGen/MIR is for testing the MIR parser/printer. Tests for passes
and targets belong to test/CodeGen/TARGETNAME.

llvm-svn: 322925
2018-01-19 06:08:15 +00:00
Puyan Lotfi fe6c9cbb24 [MIR] Repurposing '$' sigil used by external symbols. Replacing with '&'.
Planning to add support for named vregs. This puts is in a conundrum since
physregs are named as well. To rectify this we need to use a sigil other than
'%' for physregs in MIR. We've settled on using '$' for physregs but first we
must repurpose it from external symbols using it, which is what this commit is
all about. We think '&' will have familiar semantics for C/C++ users.

llvm-svn: 322146
2018-01-10 00:56:48 +00:00
Francis Visoiu Mistrih dbf2c48fc7 [MIR] Add support for the frame-destroy MachineInstr flag
We are printing / parsing the `frame-setup` MachineInstr flag but not
the `frame-destroy` one.

Differential Revision: https://reviews.llvm.org/D41509

llvm-svn: 322071
2018-01-09 11:33:22 +00:00
Francis Visoiu Mistrih b213b27ee3 [YAML] Add support for non-printable characters
LLVM IR function names which disable mangling start with '\01'
(https://www.llvm.org/docs/LangRef.html#identifiers).

When an identifier like "\01@abc@" gets dumped to MIR, it is quoted, but
only with single quotes.

http://www.yaml.org/spec/1.2/spec.html#id2770814:

"The allowed character range explicitly excludes the C0 control block
allowed), the surrogate block #xD800-#xDFFF, #xFFFE, and #xFFFF."

http://www.yaml.org/spec/1.2/spec.html#id2776092:

"All non-printable characters must be escaped.
[...]
Note that escape sequences are only interpreted in double-quoted scalars."

This patch adds support for printing escaped non-printable characters
between double quotes if needed.

Should also fix PR31743.

Differential Revision: https://reviews.llvm.org/D41290

llvm-svn: 320996
2017-12-18 17:38:03 +00:00
Francis Visoiu Mistrih 5de20e039e [MIR] Add support for missing CFI directives
The following CFI directives are suported by MC but not by MIR:

* .cfi_rel_offset
* .cfi_adjust_cfa_offset
* .cfi_escape
* .cfi_remember_state
* .cfi_restore_state
* .cfi_undefined
* .cfi_register
* .cfi_window_save

Add support for printing, parsing and update tests.

Differential Revision: https://reviews.llvm.org/D41230

llvm-svn: 320819
2017-12-15 15:17:18 +00:00
Adrian Prantl 46af7316ea Ignore metainstructions during the shrink wrap analysis
Shrink wrapping should ignore DBG_VALUEs referring to frame indices,
since the presence of debug information must not affect code
generation.

Differential Revision: https://reviews.llvm.org/D41187

llvm-svn: 320606
2017-12-13 19:10:54 +00:00
Geoff Berry 60c431022e [MachineOperand][MIR] Add isRenamable to MachineOperand.
Summary:
Add isRenamable() predicate to MachineOperand.  This predicate can be
used by machine passes after register allocation to determine whether it
is safe to rename a given register operand.  Register operands that
aren't marked as renamable may be required to be assigned their current
register to satisfy constraints that are not captured by the machine
IR (e.g. ABI or ISA constraints).

Reviewers: qcolombet, MatzeB, hfinkel

Subscribers: nemanjai, mcrosier, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D39400

llvm-svn: 320503
2017-12-12 17:53:59 +00:00
Mikael Holmen b5deac444d Skip DBG instr in OptimizePHIs when looking for dead PHI cycles
Summary:
Changed use_instructions() to use_nodbg_instructions() when
building an instruction set.

We don't want the presence of debug info to affect the code
we generate.

Reviewers: dblaikie, Eugene.Zelenko, chandlerc, aprantl

Reviewed By: aprantl

Subscribers: aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D40882

llvm-svn: 320010
2017-12-07 07:01:21 +00:00
Francis Visoiu Mistrih 25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Francis Visoiu Mistrih c71cced0aa [CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.

Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.

Differential Revision: https://reviews.llvm.org/D40421

llvm-svn: 319445
2017-11-30 16:12:24 +00:00
Oren Ben Simhon fa582b075c Control-Flow Enforcement Technology - Shadow Stack support (LLVM side)
Shadow stack solution introduces a new stack for return addresses only.
The HW has a Shadow Stack Pointer (SSP) that points to the next return address.
If we return to a different address, an exception is triggered.
The shadow stack is managed using a series of intrinsics that are introduced in this patch as well as the new register (SSP).
The intrinsics are mapped to new instruction set that implements CET mechanism.

The patch also includes initial infrastructure support for IBT.

For more information, please see the following:
https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf

Differential Revision: https://reviews.llvm.org/D40223

Change-Id: I4daa1f27e88176be79a4ac3b4cd26a459e88fed4
llvm-svn: 318996
2017-11-26 13:02:45 +00:00
Bjorn Pettersson a42ed3e361 [MIRPrinter] Use %subreg.xxx syntax for subregister index operands
Summary:
Print %subreg.<subregidxname> instead of just the subregister
index when printing immediate operands corresponding to subreg
indices in INSERT_SUBREG, EXTRACT_SUBREG, SUBREG_TO_REG and
REG_SEQUENCE.

Reviewers: qcolombet, MatzeB

Reviewed By: MatzeB

Subscribers: nhaehnle, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D39696

llvm-svn: 317513
2017-11-06 21:46:06 +00:00
Justin Bogner 6c452834a1 MIR: Print the register class or bank in vreg defs
This updates the MIRPrinter to include the regclass when printing
virtual register defs, which is already valid syntax for the
parser. That is, given 64 bit %0 and %1 in a "gpr" regbank,

  %1(s64) = COPY %0(s64)

would now be written as

  %1:gpr(s64) = COPY %0(s64)

While this change alone introduces a bit of redundancy with the
registers block, it allows us to update the tests to be more concise
and understandable and brings us closer to being able to remove the
registers block completely.

Note: We generally only print the class in defs, but there is one
exception. If there are uses without any defs whatsoever, we'll print
the class on all uses. I'm not completely convinced this comes up in
meaningful machine IR, but for now the MIRParser and MachineVerifier
both accept that kind of stuff, so we don't want to have a situation
where we can print something we can't parse.

llvm-svn: 316479
2017-10-24 18:04:54 +00:00
Justin Bogner d45849f703 Canonicalize a large number of mir tests using update_mir_test_checks
This converts a large and somewhat arbitrary set of tests to use
update_mir_test_checks. I ran the script on all of the tests I expect
to need to modify for an upcoming mir syntax change and kept the ones
that obviously didn't change the tests in ways that might make it
harder to understand.

llvm-svn: 316137
2017-10-18 23:18:12 +00:00
Mikael Holmen a079ef68e3 [RegisterCoalescer] Don't set read-undef in pruneValues, only clear
Summary:
The comments in the code said

 // Remove <def,read-undef> flags. This def is now a partial redef.

but the code didn't just remove read-undef, it could introduce new ones which
could cause errors.

E.g. if we have something like

%vreg1<def> = IMPLICIT_DEF
%vreg2:subreg1<def, read-undef> = op %vreg3, %vreg4
%vreg2:subreg2<def> = op %vreg6, %vreg7

and we merge %vreg1 and %vreg2 then we should not set undef on the second subreg
def, which the old code did.

Now we solve this by actually do what the code comment says. We remove
read-undef flags rather than remove or introduce them.

Reviewers: qcolombet, MatzeB

Reviewed By: MatzeB

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38616

llvm-svn: 315564
2017-10-12 06:21:28 +00:00
Mikael Holmen a1a3f5c5e6 Recommit [UnreachableBlockElim] Use COPY if PHI input is undef
This time invoking llc with "-march=x86-64" in the testcase, so we don't assume
the default target is x86.

Summary:
If we have

    %vreg0<def> = PHI %vreg2<undef>, <BB#0>, %vreg3, <BB#2>; GR32:%vreg0,%vreg2,%vreg3
    %vreg3<def,tied1> = ADD32ri8 %vreg0<kill,tied0>, 1, %EFLAGS<imp-def>; GR32:%vreg3,%vreg0

then we can't just change %vreg0 into %vreg3, since %vreg2 is actually
undef. We would have to also copy the undef flag to be able to change the
register.

Instead we deal with this case like other cases where we can't just
replace the register: we insert a COPY. The code creating the COPY already
copied all flags from the PHI input, so the undef flag will be transferred
as it should.

Reviewers: kparzysz

Reviewed By: kparzysz

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38235

llvm-svn: 314882
2017-10-04 07:42:45 +00:00
Mikael Holmen 75b1992f78 Revert r314879 "[UnreachableBlockElim] Use COPY if PHI input is undef"
Build-bots broke on the new testcase. I'll investigate and fix.

llvm-svn: 314880
2017-10-04 06:39:22 +00:00
Mikael Holmen 65eb2f394c [UnreachableBlockElim] Use COPY if PHI input is undef
Summary:
If we have

    %vreg0<def> = PHI %vreg2<undef>, <BB#0>, %vreg3, <BB#2>; GR32:%vreg0,%vreg2,%vreg3
    %vreg3<def,tied1> = ADD32ri8 %vreg0<kill,tied0>, 1, %EFLAGS<imp-def>; GR32:%vreg3,%vreg0

then we can't just change %vreg0 into %vreg3, since %vreg2 is actually
undef. We would have to also copy the undef flag to be able to change the
register.

Instead we deal with this case like other cases where we can't just
replace the register: we insert a COPY. The code creating the COPY already
copied all flags from the PHI input, so the undef flag will be transferred
as it should.

Reviewers: kparzysz

Reviewed By: kparzysz

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38235

llvm-svn: 314879
2017-10-04 06:06:31 +00:00
Matthias Braun 5c3e8a450e MIR: Serialize CaleeSavedInfo Restored flag
llvm-svn: 314449
2017-09-28 18:52:14 +00:00
Quentin Colombet d652aeb144 [MIRPrinter] Print empty successor lists when they cannot be guessed
This re-applies commit r313685, this time with the proper updates to
the test cases.

Original commit message:
Unreachable blocks in the machine instr representation are these
weird empty blocks with no successors.
The MIR printer used to not print empty lists of successors. However,
the MIR parser now treats non-printed list of successors as "please
guess it for me". As a result, the parser tries to guess the list of
successors and given the block is empty, just assumes it falls through
the next block (if any).

For instance, the following test case used to fail the verifier.
The MIR printer would print

         entry
        /      \
   true (def)   false (no list of successors)
       |
 split.true (use)

The MIR parser would understand this:

         entry
        /      \
   true (def)   false
       |        /  <-- invalid edge
 split.true (use)

Because of the invalid edge, we get the "def does not
dominate all uses" error.

The fix consists in printing empty successor lists, so that the parser
knows what to do for unreachable blocks.

rdar://problem/34022159

llvm-svn: 313696
2017-09-19 23:34:12 +00:00
Quentin Colombet 6888dbcda7 Revert "[MIRPrinter] Print empty successor lists when they cannot be guessed"
This reverts commit r313685.

I thought I had ran ninja check, but apparently I didn't...
Need to update a bunch of mir tests.

llvm-svn: 313686
2017-09-19 22:03:50 +00:00
Quentin Colombet 7fdaa5e641 [MIRPrinter] Print empty successor lists when they cannot be guessed
Unreachable blocks in the machine instr representation are these
weird empty blocks with no successors.
The MIR printer used to not print empty lists of successors. However,
the MIR parser now treats non-printed list of successors as "please
guess it for me". As a result, the parser tries to guess the list of
successors and given the block is empty, just assumes it falls through
the next block (if any).

For instance, the following test case used to fail the verifier.
The MIR printer would print
          entry
         /      \
    true (def)   false (no list of successors)
        |
  split.true (use)

The MIR parser would understand this:
          entry
         /      \
    true (def)   false
        |        /  <-- invalid edge
  split.true (use)

Because of the invalid edge, we get the "def does not
dominate all uses" error.

The fix consists in printing empty successor lists, so that the parser
knows what to do for unreachable blocks.

rdar://problem/34022159

llvm-svn: 313685
2017-09-19 21:55:51 +00:00
Reid Kleckner 08f5fd51cc [codeview] Generalize DIExpression parsing to handle load chains
Summary:
Hopefully this also clarifies exactly when and why we're rewriting
certiain S_LOCALs using reference types: We're using the reference type
to stand in for a zero-offset load.

Reviewers: inglorion

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37309

llvm-svn: 312247
2017-08-31 15:56:49 +00:00
Bob Haarman 223303c5a3 Reland r311957 [codeview] support more DW_OPs for more complete debug info
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

llvm-svn: 312034
2017-08-29 20:59:25 +00:00
Bob Haarman 0bf0d66682 Revert "[codeview] support more DW_OPs for more complete debug info"
This reverts commit e160912f53f047bc97e572add179e08e33f4df48.

llvm-svn: 311977
2017-08-29 04:08:31 +00:00
Bob Haarman b2a04a1513 [codeview] support more DW_OPs for more complete debug info
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

llvm-svn: 311957
2017-08-29 00:06:59 +00:00
Reid Kleckner 6d353348e5 Parse and print DIExpressions inline to ease IR and MIR testing
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

llvm-svn: 311594
2017-08-23 20:31:27 +00:00