begin at DEF slots. Fixes the second half of PR8813.

llvm-svn: 122225

llvm-svn: 122224

ARM (and other 32-bit-only) targets support for i8 and i16 overflow 
multiplies.  The generated code isn't great, but this at least fixes
CodeGen/Generic/overflow.ll when running on ARM hosts.

llvm-svn: 122221

the register; it may be a dead def instead. Fixes PR8820.

llvm-svn: 122218

Imagine we see:

EFLAGS = inst1
EFLAGS = inst2 FLAGS
gpr = inst3 EFLAGS

Previously, we would refuse to schedule inst2 because it clobbers
the EFLAGS of the predecessor.  However, it also uses the EFLAGS
of the predecessor, so it is safe to emit.  SDep edges ensure that
the right order happens already anyway.

This fixes 2 testsuite crashes with the X86 patch I'm going to
commit next.

llvm-svn: 122211

llvm-svn: 122209

llvm-svn: 122208

PR8822.

llvm-svn: 122207

half of PR8813.

llvm-svn: 122205

ConnectedVNInfoEqClasses::Classify().

llvm-svn: 122202

llvm-svn: 122199

llvm-svn: 122197

llvm-svn: 122193

enough to teach it that ADDE(0,0) is known 0 except the 
low bit, for example.

llvm-svn: 122191

alternative register allocator that does not require LiveIntervals by specifying
it on the command-line for a target that has StrongPHIElimination enabled by
default.

These checks are pretty meaningless anyways, since StrongPHIElimination and
PHIElimination are never used at the same time.

llvm-svn: 122176

isel is *required* to split the edge.  PHI values get evaluated
on the edge, not in their predecessor block.

llvm-svn: 122170

llvm-svn: 122135

use before rematerializing the load.

This allows us to produce:

    addps	LCPI0_1(%rip), %xmm2

Instead of:

    movaps	LCPI0_1(%rip), %xmm3
    addps	%xmm3, %xmm2

Saving a register and an instruction. The standard spiller already knows how to
do this.

llvm-svn: 122133

llvm-svn: 122132

the loop predecessors.

The register can be live-out from a predecessor without being live-in to the
loop header if there is a critical edge from the predecessor.

llvm-svn: 122123

  lib/CodeGen/RegAllocGreedy.cpp:311: error: unused variable 'PhysReg' [-Wunused-variable]

llvm-svn: 122122

createMachineVerifierPass and MachineFunction::verify.

The banner is printed before the machine code dump, just like the printer pass.

llvm-svn: 122113

interference.

llvm-svn: 122108

RegAllocBase::VerifyEnabled.

Run the machine code verifier in a few interesting places during RegAllocGreedy.

llvm-svn: 122107

The heuristics split around the largest loop where the current register may be
allocated without interference.

llvm-svn: 122106

may be called. If the entry block is empty, the insertion point iterator will be
the "end()" value. Calling ->getParent() on it (among others) causes problems.

Modify materializeFrameBaseRegister to take the machine basic block and insert
the frame base register at the beginning of that block. (It's very similar to
what the code does all ready. The only difference is that it will always insert
at the beginning of the entry block instead of after a previous materialization
of the frame base register. I doubt that that matters here.)

<rdar://problem/8782198>

llvm-svn: 122104

BUILD_VECTOR operands where the element type is not legal.  I had previously
changed this code to insert TRUNCATE operations, but that was just wrong.

llvm-svn: 122102

code for the case where 32-bit divide by constant is
turned into 64-bit multiply by constant.  8771012.

llvm-svn: 122090

the operand uses the same register as a tied operand:

  %r1 = add %r1, %r1

If add were a three-address instruction, kill flags would be required on at
least one of the uses. Since it is a two-address instruction, the tied use
operand must not have a kill flag.

This change makes the kill flag on the untied use operand optional.

llvm-svn: 122082

llvm-svn: 122073

This is a three-way interval list intersection between a virtual register, a
live interval union, and a loop. It will be used to identify interference-free
loops for live range splitting.

llvm-svn: 122034

Radar 8776599

llvm-svn: 122018

llvm-svn: 122016

 - Treaty talks on the non-proliferation of MC objects broke down.

llvm-svn: 121949

live range splitting around loops guided by register pressure.

So far, trySplit() simply prints a lot of debug output.

llvm-svn: 121918

A MachineLoopRange contains the intervals of slot indexes covered by the blocks
in a loop. This representation of the loop blocks is more efficient to compare
against interfering registers during register coalescing.

llvm-svn: 121917

llvm-svn: 121903

function so that it can live in Analysis instead of
VMCore.

llvm-svn: 121885

llvm-svn: 121872

Bypass loops have the current live range live through, but contain no uses or
defs. Splitting around a bypass loop can free registers for other uses inside
the loop by spilling the split range.

llvm-svn: 121871