This only affects targets like Mips where branch instructions may kill virtual
registers. Most other targets branch on flag values, so virtual registers are
not involved.
The problem is that MachineBasicBlock::updateTerminator deletes branches and
inserts new ones while LiveVariables keeps a list of pointers to instructions
that kill virtual registers. That list wasn't properly updated in
MBB::SplitCriticalEdge.
llvm-svn: 132298
This is important for the correct lowering of unwind instructions
(which doesn't matter at all) and llvm.eh.resume calls (which does).
Take 2, now with more basic competence.
llvm-svn: 132295
This is important for the correct lowering of unwind instructions
(which doesn't matter at all) and llvm.eh.resume calls (which does).
llvm-svn: 132291
variable. Noticed by inspection.
Simulate memset in EvaluateFunction where the target of the memset and the
value we're setting are both the null value. Fixes PR10047!
llvm-svn: 132288
handler.
At this moment, only GCC-style exceptions are supported. Other kinds
of exceptions, including "traditional" SEH and Microsoft Visual C++ exceptions,
need more work--and an compiler exception model that isn't specific to
GCC-style exceptions!
In particular, I imagine that it would be possible to mix "traditional" SEH
with GCC-style EH or Microsoft C++ EH. Currently LLVM has no way (beyond some
target-specific defaults and whole-module compiler switches) of knowing which
scheme to use when.
llvm-svn: 132283
This patch does not change the behavior of the type legalizer. The codegen
produces the same code.
This infrastructural change is needed in order to enable complex decisions
for vector types (needed by the vector-select patch).
llvm-svn: 132263
transformed by the inliner into a branch to the enclosing landing pad
(when inlined through an invoke). If not so optimized, it is lowered
DWARF EH preparation into a call to _Unwind_Resume (or _Unwind_SjLj_Resume
as appropriate). Its chief advantage is that it takes both the
exception value and the selector value as arguments, meaning that there
is zero effort in recovering these; however, the frontend is required
to pass these down, which is not actually particularly difficult.
Also document the behavior of landing pads a bit better, and make it
clearer that it's okay that personality functions don't always land at
landing pads. This is just a fact of life. Don't write optimizations that
rely on pushing things over an unwind edge.
llvm-svn: 132253
switch. With this newfound organization, teach tblgen how not to give
all intrinsics the 'nounwind' attribute. Introduce a new intrinsic,
llvm.eh.resume, which does not have this attribute. Documentation and uses
to follow.
llvm-svn: 132252
to load/store i64 values. Since there's no current support to explicitly
declare such restrictions, implement it by using specific hardcoded register
pairs during isel.
llvm-svn: 132248
Delete the Kill and Def markers in BlockInfo. They are no longer
necessary when BlockInfo describes a continuous live range.
This only affects the relatively rare kind of basic block where a live
range looks like this:
|---x o---|
Now live range splitting can pretend that it is looking at two blocks:
|---x
o---|
This allows the code to be simplified a bit.
llvm-svn: 132245
It is important that this function returns the same number of live blocks as
countLiveBlocks(CurLI) because live range splitting uses the number of live
blocks to ensure it is making progress.
This is in preparation of supporting duplicate UseBlock entries for basic blocks
that have a virtual register live-in and live-out, but not live-though.
llvm-svn: 132244
register allocation dependent and will occasionally break. WIP in the
register allocator to model paired/etc registers.
rdar://9119939
llvm-svn: 132242
There was no way to check if a given register/mode pair was valid. We now return
an error code (-2) instead of asserting. If anyone thinks that an assert
at this point is really needed, we can autogen a hasValidDwarfRegNum instead.
llvm-svn: 132236
was saying that the matching superregister class of GR32_NOREX in GR64_NOREX_NOSP
is GR64_NOREX, which drops the NOSP constraint. This fixes PR10032.
llvm-svn: 132225
subregisters:
When a value is in a subregister, at least report the location as being
the superregister. We should extend the .td files to encode the bit
range so that we can produce a DW_OP_bit_piece.
llvm-svn: 132224
