Commit Graph

18 Commits

Author SHA1 Message Date
Reid Kleckner 7850c9f5ca [WinEH] Make llvm.x86.seh.recoverfp work on x64
It adjusts from RSP-after-prologue to RBP, which is what SEH filters
need to do before they can use llvm.localrecover.

Fixes SEH filter captures, which were broken in r250088.

Issue reported by Alex Crichton.

llvm-svn: 255707
2015-12-15 23:40:58 +00:00
David Majnemer 3bb88c0210 [WinEH] Use operand bundles to describe call sites
SimplifyCFG allows tail merging with code which terminates in
unreachable which, in turn, makes it possible for an invoke to end up in
a funclet which it was not originally part of.

Using operand bundles on invokes allows us to determine whether or not
an invoke was part of a funclet in the source program.

Furthermore, it allows us to unambiguously answer questions about the
legality of inlining into call sites which the personality may have
trouble with.

Differential Revision: http://reviews.llvm.org/D15517

llvm-svn: 255674
2015-12-15 21:27:27 +00:00
David Majnemer 8a1c45d6e8 [IR] Reformulate LLVM's EH funclet IR
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
  but they are difficult to explain to others, even to seasoned LLVM
  experts.
- catchendpad and cleanupendpad are optimization barriers.  They cannot
  be split and force all potentially throwing call-sites to be invokes.
  This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
  It is unsplittable, starts a funclet, and has control flow to other
  funclets.
- The nesting relationship between funclets is currently a property of
  control flow edges.  Because of this, we are forced to carefully
  analyze the flow graph to see if there might potentially exist illegal
  nesting among funclets.  While we have logic to clone funclets when
  they are illegally nested, it would be nicer if we had a
  representation which forbade them upfront.

Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
  flow, just a bunch of simple operands;  catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
  the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
  the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad.  Their presence can be inferred
  implicitly using coloring information.

N.B.  The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for.  An expert should take a
look to make sure the results are reasonable.

Reviewers: rnk, JosephTremoulet, andrew.w.kaylor

Differential Revision: http://reviews.llvm.org/D15139

llvm-svn: 255422
2015-12-12 05:38:55 +00:00
David Majnemer 2652b75700 [WinEH] Don't emit CATCHRET from visitCatchPad
Instead, emit a CATCHPAD node which will get selected to a target
specific sequence.

llvm-svn: 252528
2015-11-09 23:07:48 +00:00
Reid Kleckner d880dc7509 [SEH] Remember to emit the last invoke range for SEH
This wasn't very observable in execution tests, because usually there is
an invoke in the catchpad that unwinds the the catchendpad but never
actually throws.

llvm-svn: 249898
2015-10-09 20:39:39 +00:00
David Majnemer a80c151286 [WinEH] Teach AsmPrinter about funclets
Summary:
Funclets have been turned into functions by the time they hit the object
file.  Make sure that they have decent names for the symbol table and
CFI directives explaining how to reason about their prologues.

Differential Revision: http://reviews.llvm.org/D13261

llvm-svn: 248824
2015-09-29 20:12:33 +00:00
David Majnemer 7fddeccb8b Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00
Reid Kleckner a9d6253572 [WinEH] Create an llvm.x86.seh.exceptioninfo intrinsic
This intrinsic is like framerecover plus a load. It recovers the EH
registration stack allocation from the parent frame and loads the
exception information field out of it, giving back a pointer to an
EXCEPTION_POINTERS struct. It's designed for clang to use in SEH filter
expressions instead of accessing the EXCEPTION_POINTERS parameter that
is available on x64.

This required a minor change to MC to allow defining a label variable to
another absolute framerecover label variable.

llvm-svn: 239567
2015-06-11 22:32:23 +00:00
Reid Kleckner c87a6faba1 [WinEH] _except_handlerN uses 0 instead of 1 to indicate catch-all
Our usage of 1 was a holdover from __C_specific_handler.

llvm-svn: 239482
2015-06-10 18:14:07 +00:00
Reid Kleckner f12c030f48 [WinEH] Add 32-bit SEH state table emission prototype
This gets all the handler info through to the asm printer and we can
look at the .xdata tables now. I've convinced one small catch-all test
case to work, but other than that, it would be a stretch to say this is
functional.

The state numbering algorithm avoids doing any scope reconstruction as
we do for C++ to simplify the implementation.

llvm-svn: 239433
2015-06-09 21:42:19 +00:00
Reid Kleckner cfbfe6f29c [SEH] Implement GetExceptionCode in __except blocks
This introduces an intrinsic called llvm.eh.exceptioncode. It is lowered
by copying the EAX value live into whatever basic block it is called
from. Obviously, this only works if you insert it late during codegen,
because otherwise mid-level passes might reschedule it.

llvm-svn: 235768
2015-04-24 20:25:05 +00:00
Reid Kleckner 5c5facc2ce Re-commit "[SEH] Remove the old __C_specific_handler code now that WinEHPrepare works"
This reverts commit r235617.

r235649 should have addressed the problems.

llvm-svn: 235667
2015-04-23 23:22:33 +00:00
Reid Kleckner 909ea7e6b8 Revert "[SEH] Remove the old __C_specific_handler code now that WinEHPrepare works"
We still have some "uses remain after removal" issues in -O0 builds.

This reverts commit r235557.

llvm-svn: 235617
2015-04-23 18:34:01 +00:00
Reid Kleckner 64a2a6a473 [SEH] Remove the old __C_specific_handler code now that WinEHPrepare works
This removes the -sehprepare flag and makes __C_specific_handler
functions always to use WinEHPrepare.

This was tested by building all of chromium_builder_tests and running a
few tests that use SEH, but if something breaks, we can revert this.

llvm-svn: 235557
2015-04-22 22:13:09 +00:00
Reid Kleckner d2a1a51996 Re-land r235154-r235156 under the existing -sehprepare flag
Keep the old SEH fan-in lowering on by default for now, since projects
rely on it.  This will make it easy to test this change with a simple
flag flip.

llvm-svn: 235399
2015-04-21 18:23:57 +00:00
David Blaikie f72d05bc7b [opaque pointer type] Add textual IR support for explicit type parameter to gep operator
Similar to gep (r230786) and load (r230794) changes.

Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.

(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)

import fileinput
import sys
import re

rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)

def conv(match):
  line = match.group(1)
  line += match.group(4)
  line += ", "
  line += match.group(2)
  return line

line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
  sys.stdout.write(line[off:match.start()])
  sys.stdout.write(conv(match))
  off = match.end()
sys.stdout.write(line[off:])

llvm-svn: 232184
2015-03-13 18:20:45 +00:00
Reid Kleckner 5eb6ade35f SEH: Finish writing the catch-all test case
llvm-svn: 226768
2015-01-22 02:31:09 +00:00
Reid Kleckner f690f50519 Win64 SEH: Emit the constant 1 for catch-all into xdata
llvm-svn: 226767
2015-01-22 02:27:44 +00:00