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
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
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
The patch is generated using clang-tidy misc-use-override check.
This command was used:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
-checks='-*,misc-use-override' -header-filter='llvm|clang' \
-j=32 -fix -format
http://reviews.llvm.org/D8925
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234679 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
This makes it possible to use the same representation of llvm.eh.actions
in outlined handlers as we use in the parent function because i32's are
just constants that can be copied freely between functions.
I had to add a sentinel alloca to the list of child allocas so that we
don't try to sink the catch object into the handler. Normally, one would
use nullptr for this kind of thing, but TinyPtrVector doesn't support
null elements. More than that, it's elements have to have a suitable
alignment. Therefore, I settled on this for my sentinel:
AllocaInst *getCatchObjectSentinel() {
return static_cast<AllocaInst *>(nullptr) + 1;
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233947 91177308-0d34-0410-b5e6-96231b3b80d8
This lets us catch exceptions in simple cases.
N.B. Things that do not work include (but are not limited to):
- Throwing from within a catch handler.
- Catching an object with a named catch parameter.
- 'CatchHigh' is fictitious, we aren't sure of its purpose.
- We aren't entirely efficient with regards to the number of EH states
that we generate.
- IP-to-State tables are sensitive to the order of emission.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233767 91177308-0d34-0410-b5e6-96231b3b80d8
Generate tables in the .xdata section representing what actions to take
when an exception is thrown. This currently fills in state for
cleanups, catch handlers are still unfinished.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233636 91177308-0d34-0410-b5e6-96231b3b80d8
We don't have any logic to emit those tables yet, so the SDAG lowering
of this intrinsic is just a stub. We can see the intrinsic in the
prepared IR, though.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233354 91177308-0d34-0410-b5e6-96231b3b80d8
We don't have any logic to emit those tables yet, so the sdag lowering
of this intrinsic is just a stub. We can see the intrinsic in the
prepared IR, though.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233209 91177308-0d34-0410-b5e6-96231b3b80d8
This switches the sense of the i32 values and updates the test cases.
We can also use CHECK-SAME to clean up some tests, and reduce the visual
noise from bitcasts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232774 91177308-0d34-0410-b5e6-96231b3b80d8
These docs *don't* match the way WinEHPrepare uses them yet, and
verifier support isn't implemented either. The implementation will come
after the documentation text is reviewed and agreed upon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232003 91177308-0d34-0410-b5e6-96231b3b80d8
Instead, run both EH preparation passes, and have them both ignore
functions with unrecognized EH personalities. Pass delegation involved
some hacky code for creating an AnalysisResolver that we don't need now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231995 91177308-0d34-0410-b5e6-96231b3b80d8
