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
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
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
register allocation dependent and will occasionally break. WIP in the
register allocator to model paired/etc registers.
rdar://9119939
llvm-svn: 132242
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
According to PR2536, the old spiller had trouble with the IMPLICIT_DEF in this
code:
%reg1028<def> = MOV16rm %reg0, 1, %reg0, <ga:g_5>, Mem:LD(2,2) [g_5 + 0]
%reg1039<def> = IMPLICIT_DEF
%reg1038<def> = INSERT_SUBREG %reg1039, %reg1028, 2
%reg1025<def> = AND32ri %reg1038, 65534, %%EFLAGS<imp-def>
However, today we emit a zero-extending load instead:
%vreg10<def> = MOVZX32rm16 %noreg, 1, %noreg, <ga:@g_5>, %noreg; %mem:LD2[@g_5] GR32:%vreg10
%vreg0<def> = AND32ri %vreg10, 65534, %%EFLAGS<imp-def,dead>; %GR32:%vreg0,%vreg10
This makes the test pointless since it no longer creates the spiller hazard.
llvm-svn: 132210
- the selector for the landing pad must provide all available information
about the handlers, filters, and cleanups within that landing pad
- calls to _Unwind_Resume must be converted to branches to the enclosing
lpad so as to avoid re-entering the unwinder when the lpad claimed it
was going to handle the exception in some way
This is quite specific to libUnwind-based unwinding. In an effort to not
interfere too badly with other unwinders, and with existing hacks in frontends,
this only triggers on _Unwind_Resume (not _Unwind_Resume_or_Rethrow) and does
nothing with selectors if it cannot find a selector call for either lpad.
llvm-svn: 132200
- Flip order of bitfields. This gets our output matching GAS.
- Handle case where the end of the prolog wasn't specified.
- If the resulting unwind info struct is less than 8 bytes, pad to 8 bytes.
Add a test for the latter two.
llvm-svn: 132188
Rework how the MCWin64EHUnwindInfo instances are stored. Fix issues with
chained unwind areas exposed by the test that were related to this.
The ChainedParent field had the wrong address, because when the chained unwind
info was added, the addresses shifted around. Now we store the pointers to the
structures, which are now allocated from the MC heap.
llvm-svn: 132106
Use a proper worklist for use-def traversal without holding onto an
iterator. Now that we process all IV uses, we need complete logic for
resusing existing derived IV defs. See HoistStep.
llvm-svn: 132103
