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

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

Refactor the type legalizer. Switch TargetLowering to a new enum - LegalizeTypeAction.
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

llvm-svn: 132256

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

llvm-svn: 132250

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

llvm-svn: 132239

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

the Win64 EH mechanism to implement GCC-style exceptions. LLVM supports
hardly anything else at this point!

llvm-svn: 132234

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

llvm-svn: 132222

this. XFAIL'd, because the COFF AsmParser can't handle .section yet.

llvm-svn: 132220

code in one place. Re-apply 131534 and fix the multi-step promotion of integers.

llvm-svn: 132217

Keep this simple. Use DIType to get signness and size of a type. Based on size, select appropraite form.

llvm-svn: 132206

This fixes regressions reported by buildbots as a fallout of r132193.

llvm-svn: 132197

llvm-svn: 132193

llvm-svn: 132181

llvm-svn: 132149

llvm-svn: 132148

assert that prevented setting alignment on section creation.

llvm-svn: 132113

llvm-svn: 132111

llvm-svn: 132108

rdar://problem/6920088

llvm-svn: 132105

This doesn't change functionality (much), but it allows for a more fine-grained
eviction policy. The current policy only compares spill weights, and that is not
always the best thing to do.  Spill weights are designed to serve linear scan,
and they don't consider live range splitting.

Add a mechanism so canEvict() can request that a live range be evicted and
split/spilled. This is to avoid infinite eviction loops.

llvm-svn: 132101

Rewrite fast-isel integer cast handling to handle more cases, and to be simpler and more consistent.

The practical effects here are that x86-64 fast-isel can now handle trunc from i8 to i1, and ARM fast-isel can handle many more constructs involving integers narrower than 32 bits (including loads, stores, and many integer casts).

rdar://9437928 .

llvm-svn: 132099

llvm-svn: 132087

LTO friendly as we can now correctly merge files compiled with or without
-fasynchronous-unwind-tables.

llvm-svn: 132033

llvm-svn: 131974

llvm-svn: 131952

llvm-svn: 131951

  non-zero.
- Teach X86 cmov optimization to eliminate the cmov from ctlz, cttz extension
  when the source of X86ISD::BSR / X86ISD::BSF is proven to be non-zero.

rdar://9490949

llvm-svn: 131948

llvm-svn: 131940

llvm-svn: 131936

llvm-svn: 131926

Patch by Micah Villmow

llvm-svn: 131908

llvm-svn: 131907

when we're just going to throw the result away.  No functionality change.

llvm-svn: 131880

should eventually convert to PMBuilder, but I don't plan to do this.

llvm-svn: 131819