This in turn would sometimes introduce new cleanupblocks that didn't
previously exist. The uses were being introduced by SSA value demotion.
We actually want to *promote* uses of EH pointers and selectors, so I
added some spcecial casing to avoid demoting such instructions. This is
getting overly complicated, but hopefully we'll come along and delete it
in the new representation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241950 91177308-0d34-0410-b5e6-96231b3b80d8
Apparently this is important, otherwise _except_handler3 assumes that
the registration node is corrupted and ignores it.
Also fix a bug in WinEHPrepare where we would insert code after a
terminator instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241877 91177308-0d34-0410-b5e6-96231b3b80d8
The 32-bit lowering assumed that WinEHPrepare had this invariant.
WinEHPrepare did it for C++, but not SEH. The result was that we would
insert calls to llvm.x86.seh.restoreframe in normal basic blocks, which
corrupted the frame pointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241699 91177308-0d34-0410-b5e6-96231b3b80d8
Clang uses this for SEH finally. The new intrinsic will produce the
right value when stack realignment is required.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241643 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Initially, these intrinsics seemed like part of a family of "frame"
related intrinsics, but now I think that's more confusing than helpful.
Initially, the LangRef specified that this would create a new kind of
allocation that would be allocated at a fixed offset from the frame
pointer (EBP/RBP). We ended up dropping that design, and leaving the
stack frame layout alone.
These intrinsics are really about sharing local stack allocations, not
frame pointers. I intend to go further and add an `llvm.localaddress()`
intrinsic that returns whatever register (EBP, ESI, ESP, RBX) is being
used to address locals, which should not be confused with the frame
pointer.
Naming suggestions at this point are welcome, I'm happy to re-run sed.
Reviewers: majnemer, nicholas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11011
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241633 91177308-0d34-0410-b5e6-96231b3b80d8
We support invoking a subset of llvm's intrinsics, but the verifier didn't account for this. We had previously added a special case to verify invokes of statepoints. By generalizing the code in terms of CallSite, we can verify invokes of other intrinsics as well. Interestingly, this found one test case which was invalid.
Note: I'm deliberately leaving the naming change from CI to CS to a follow up change. That will happen shortly, I just wanted to reduce the diff to make it clear what was happening with this one.
Differential Revision: http://reviews.llvm.org/D10118
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240836 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239940 91177308-0d34-0410-b5e6-96231b3b80d8
32-bit x86 MSVC-style exceptions are functionaly similar to 64-bit, but
they take no arguments. Instead, they implicitly use the value of EBP
passed in by the caller as a pointer to the parent's frame. In LLVM, we
can represent this as llvm.frameaddress(1), and feed that into all of
our calls to llvm.framerecover.
The next steps are:
- Add an alloca to the fs:00 linked list of handlers
- Add something like llvm.sjlj.lsda or generalize it to store in the
alloca
- Move state number calculation to WinEHPrepare, arrange for
FunctionLoweringInfo to call it
- Use the state numbers to insert explicit loads and stores in the IR
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236172 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235768 91177308-0d34-0410-b5e6-96231b3b80d8
Same as r235145 for the call instruction - the justification, tradeoffs,
etc are all the same. The conversion script worked the same without any
false negatives (after replacing 'call' with 'invoke').
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235755 91177308-0d34-0410-b5e6-96231b3b80d8
We were asserting on code like this:
extern "C" unsigned long _exception_code();
void might_crash(unsigned long);
void foo() {
__try {
might_crash(0);
} __except(1) {
might_crash(_exception_code());
}
}
Gtest and many other libraries get the exception code from the __except
block. What's supposed to happen here is that EAX is live into the
__except block, and it contains the exception code. Eventually we'll
represent that as a use of the landingpad ehptr value, but for now we
can replace it with undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235649 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235557 91177308-0d34-0410-b5e6-96231b3b80d8
In particular, this handles SSA values that are live *out* of a handler.
The existing code only handles values that are live *in* to a handler.
It also handles phi nodes in the block where normal control should
resume after the end of a catch handler. When EH return points have phi
nodes, we need to split the return edge. It is impossible for phi
elimination to emit copies in the previous block if that block gets
outlined. The indirectbr that we leave in the function is only notional,
and is eliminated from the MachineFunction CFG early on.
Reviewers: majnemer, andrew.w.kaylor
Differential Revision: http://reviews.llvm.org/D9158
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235545 91177308-0d34-0410-b5e6-96231b3b80d8
We should also teach the inliner to collapse framerecover of
frameaddress of the current frame down to an alloca, but that can happen
later.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235459 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235399 91177308-0d34-0410-b5e6-96231b3b80d8
This now emits simple, unoptimized xdata tables for __C_specific_handler
based on the handlers listed in @llvm.eh.actions calls produced by
WinEHPrepare.
This adds support for running __finally blocks when exceptions are
thrown, and removes the old landingpad fan-in codepath.
I ran some manual execution tests on small basic test cases with and
without optimization, as well as on Chrome base_unittests, which uses a
small amount of SEH. I'm sure there are bugs, and we may need to
revert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235154 91177308-0d34-0410-b5e6-96231b3b80d8
See r230786 and r230794 for similar changes to gep and load
respectively.
Call is a bit different because it often doesn't have a single explicit
type - usually the type is deduced from the arguments, and just the
return type is explicit. In those cases there's no need to change the
IR.
When that's not the case, the IR usually contains the pointer type of
the first operand - but since typed pointers are going away, that
representation is insufficient so I'm just stripping the "pointerness"
of the explicit type away.
This does make the IR a bit weird - it /sort of/ reads like the type of
the first operand: "call void () %x(" but %x is actually of type "void
()*" and will eventually be just of type "ptr". But this seems not too
bad and I don't think it would benefit from repeating the type
("void (), void () * %x(" and then eventually "void (), ptr %x(") as has
been done with gep and load.
This also has a side benefit: since the explicit type is no longer a
pointer, there's no ambiguity between an explicit type and a function
that returns a function pointer. Previously this case needed an explicit
type (eg: a function returning a void() function was written as
"call void () () * @x(" rather than "call void () * @x(" because of the
ambiguity between a function returning a pointer to a void() function
and a function returning void).
No ambiguity means even function pointer return types can just be
written alone, without writing the whole function's type.
This leaves /only/ the varargs case where the explicit type is required.
Given the special type syntax in call instructions, the regex-fu used
for migration was a bit more involved in its own unique way (as every
one of these is) so here it is. Use it in conjunction with the apply.sh
script and associated find/xargs commands I've provided in rr230786 to
migrate your out of tree tests. Do let me know if any of this doesn't
cover your cases & we can iterate on a more general script/regexes to
help others with out of tree tests.
About 9 test cases couldn't be automatically migrated - half of those
were functions returning function pointers, where I just had to manually
delete the function argument types now that we didn't need an explicit
function type there. The other half were typedefs of function types used
in calls - just had to manually drop the * from those.
import fileinput
import sys
import re
pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)')
addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$")
func_end = re.compile("(?:void.*|\)\s*)\*$")
def conv(match, line):
if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)):
return line
return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():]
for line in sys.stdin:
sys.stdout.write(conv(re.search(pat, line), line))
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235145 91177308-0d34-0410-b5e6-96231b3b80d8
The way we split SEH catch-all blocks can leave some dead EH values
behind at -O0. Try to remove them, and if we fail, replace them all with
undef.
Fixes a crash when removing the old unreachable landingpad which is
still used by extractvalue instructions in the catch-all block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235061 91177308-0d34-0410-b5e6-96231b3b80d8
This avoids emitting code for unreachable landingpad blocks that contain
calls to llvm.eh.actions and indirectbr.
It's also a first step towards unifying the SEH and WinEH lowering
codepaths. I'm keeping the old fan-in lowering of SEH around until the
preparation version works well enough that we can switch over without
breaking existing users.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235037 91177308-0d34-0410-b5e6-96231b3b80d8
Since adding invokes of llvm.donothing to cleanups, we come here now,
and trivial EH cleanup usage from clang fails to compile.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234948 91177308-0d34-0410-b5e6-96231b3b80d8
This allows winehprepare to build sensible llvm.eh.actions calls for SEH
finally blocks. The pattern matching in this change is brittle and
should be replaced with something more robust soon. In the meantime,
this will let us write the code that produces __C_specific_handler xdata
tables, which we need regardless of how we decide to get finally blocks
through EH preparation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234663 91177308-0d34-0410-b5e6-96231b3b80d8
WinEH currently turns invokes into calls. Long term, we will reconsider
this, but for now, make sure we remap the operands and clone the
successors of the new terminator.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234608 91177308-0d34-0410-b5e6-96231b3b80d8
Fixed insert point for allocas created for demoted values.
Clear the nested landing pad list after it has been processed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234433 91177308-0d34-0410-b5e6-96231b3b80d8
The uselist isn't enough to infer anything about the lifetime of such
allocas. If we want to re-add this optimization, we will need to
leverage lifetime markers to do it.
Fixes PR23122.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234196 91177308-0d34-0410-b5e6-96231b3b80d8
This add support for catching an exception such that an exception object
available to the catch handler will be initialized by the runtime.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234062 91177308-0d34-0410-b5e6-96231b3b80d8
We don't need to represent UnwindHelp in IR. Instead, we can use the
knowledge that we are emitting the parent function to decide if we
should create the UnwindHelp stack object.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234061 91177308-0d34-0410-b5e6-96231b3b80d8