This function does more or less the same as
MI::readsWritesVirtualRegister(), but it supports bundles as well.

It also determines if any constraint requires reading and writing
operands to use the same register.  Most clients want to know.

Use the more modern MO.readsReg() instead of trying to sort out undefs
and partial redefines.  Stop supporting the extra full <imp-def> operand
as an alternative to <def,undef> sub-register defines.

llvm-svn: 151690

Extract a base class and provide four specific sub-classes for iterating
over const/non-const bundles/instructions.

This eliminates the mystery bool constructor argument.

llvm-svn: 151684

methods are no longer needed now that LinearScan has gone away.

(Contains tweaks trivialSpillEverywhere to enable the removal of getNewVRegs).

llvm-svn: 151658

llvm-svn: 151645

llvm-svn: 151644

To avoid problems with zero shifts when getting the bits that move between words
we use a trick: first shift the by amount-1, then do another shift by one. When
amount is 0 (and size 32) we first shift by 31, then by one, instead of by 32.

Also fix a latent bug that emitted the low and high words in the wrong order
when shifting right.

Fixes PR12113.

llvm-svn: 151637

Revert r151623 "Some ARM implementaions, e.g. A-series, does return stack prediction. ...", it is breaking the Clang build during the Compiler-RT part.

llvm-svn: 151630

llvm-svn: 151627

When the GEP index is a vector of pointers, the code that calculated the size
of the element started from the vector type, and not the contained pointer type.
As a result, instead of looking at the data element pointed by the vector, this
code used the size of the vector. This works for 32bit members (on 32bit
systems), but not for other types. Added code to peel the vector type and
added a test.

llvm-svn: 151626

the processor keeps a return addresses stack (RAS) which stores the address
and the instruction execution state of the instruction after a function-call
type branch instruction.

Calling a "noreturn" function with normal call instructions (e.g. bl) can
corrupt RAS and causes 100% return misprediction so LLVM should use a
unconditional branch instead. i.e.
mov lr, pc
b _foo
The "mov lr, pc" is issued in order to get proper backtrace.

rdar://8979299

llvm-svn: 151623

Don't attempt to extend physreg live ranges across calls.

<rdar://problem/10942095>

llvm-svn: 151610

llvm-svn: 151607

llvm-svn: 151599

%S5<def> = COPY %S0<kill>
First clear def map of Q1, etc.

No small test case available.

llvm-svn: 151574

After the SlotIndex slot names were updated, it is possible to apply
stricter checks to live intervals.

Also treat bundles as bags of operands when checking live intervals.

llvm-svn: 151531

uses of the vreg, since the old kills may no longer be valid.  This was causing
-verify-machineinstrs to complain about uses after kills, and could potentially
have been causing subtle register allocation issues, but I haven't come across a
test case yet.

llvm-svn: 151425

llvm-svn: 151417

llvm-svn: 151396

This will limit all register classes to N registers in order to stress
test register allocation.

llvm-svn: 151379

This is necessary to support the existing ppc lowering code for indirect calls.
Fixes PR12071.

llvm-svn: 151373

llvm-svn: 151364

llvm-svn: 151355

llvm-svn: 151348

Turn avx insert intrinsic calls into INSERT_SUBVECTOR DAG nodes and remove duplicate patterns for selecting the intrinsics

llvm-svn: 151342

variable declaration as an argument because we want that address
anyhow for our debug information.

This seems to fix rdar://9965111, at least we have more debug
information than before and from reading the assembly it appears
to be the correct location.

llvm-svn: 151335

llvm-svn: 151334

asm.
<rdar://problem/10106006>

llvm-svn: 151303

llvm-svn: 151274

Rename it to LiveRegs to make it more clear what's stored inside.

llvm-svn: 151273

Assuming that a single std::set node adds 3 control words, a bitvector
can store (3*8+4)*8=224 registers in the allocated memory of a single
element in the std::set (x86_64). Also we don't have to call malloc
for every register added.

llvm-svn: 151269

Before register allocation, instructions can be moved across calls in
order to reduce register pressure.  After register allocation, we don't
gain a lot by moving callee-saved defs across calls.  In fact, since the
scheduler doesn't have a good idea how registers are used in the callee,
it can't really make good scheduling decisions.

This changes the schedule in two ways: 1. Latencies to call uses and
defs are no longer accounted for, causing some random shuffling around
calls.  This isn't really a problem since those uses and defs are
inaccurate proxies for what happens inside the callee.  They don't
represent registers used by the call instruction itself.

2. Instructions are no longer moved across calls.  This didn't happen
very often, and the scheduling decision was made on dubious information
anyway.

As with any scheduling change, benchmark numbers shift around a bit,
but there is no positive or negative trend from this change.

This makes the post-ra scheduler 5% faster for ARM targets.

The secret motivation for this patch is the introduction of register
mask operands representing call clobbers.  The most efficient way of
handling regmasks in ScheduleDAGInstrs is to model them as barriers for
physreg live ranges, but not for virtreg live ranges.  That's fine
pre-ra, but post-ra it would have the same effect as this patch.

llvm-svn: 151265

llvm-svn: 151252

of instantiated C++ templates.

Patch by Kristof Beyls!

llvm-svn: 151250

llvm-svn: 151235

llvm-svn: 151234

Ignore undef uses completely.
Use a more explicit SlotIndex API.
Add more explicit comments.

llvm-svn: 151233

Added array subscript to SparseSet for convenience.
Slight reorg to make it easier to manage the def/use sets.

llvm-svn: 151228

llvm-svn: 151226

llvm-svn: 151223

The bulk masking operations from register mask operands don't account
for reserved registers.

llvm-svn: 151222