from physical registers, and they are always dense, it makes sense to not have
a ton of RBtree overhead.  This change speeds up regalloclocal about ~30% on
253.perlbmk, from .35s -> .27s in the JIT (in LLC, it goes from .74 -> .55).

Now live variable analysis is the slowest codegen pass.  Of course it doesn't
help that we have to run it twice, because regalloclocal doesn't update it,
but even if it did it would be the slowest pass (now it's just the 2x slowest
pass :(

llvm-svn: 11215

llvm-svn: 11151

of the virtual register to certain functions.

llvm-svn: 11143

slots each. As a concequence they get numbered as 0, 2, 4 and so
on. The first slot is used for operand uses and the second for
defs. Here's an example:

0: A = ...
2: B = ...
4: C = A + B ;; last use of A

The live intervals should look like:

A = [1, 5)
B = [3, x)
C = [5, y)

llvm-svn: 11141

access. Rather we only have to do it on the creation of the interval.

llvm-svn: 11135

llvm-svn: 11129

operand of the instruction and thus simplify the register allocation.

llvm-svn: 11124

spilled, A was loaded from its stack location twice. This fixes the bug.

llvm-svn: 11093

llvm-svn: 11091

llvm-svn: 11088

llvm-svn: 11087

outside of loops = 0.

llvm-svn: 11085

much better when I get rid of the reserved registers.

llvm-svn: 11066

registers (not as the max number of registers).

Change toSpill from a std::set into a std::vector<bool>.

Use the reverse iterator adapter to do a reverse scan of allocatable
registers.

llvm-svn: 11061

where appropriate.

llvm-svn: 11060

llvm-svn: 11057

llvm-svn: 11054

llvm-svn: 11050

llvm-svn: 11048

llvm-svn: 11047

MRegisterInfo::isVirtualRegister.

llvm-svn: 11045

llvm-svn: 11040

llvm-svn: 11038

method

llvm-svn: 11037

Fix a spello
Tighten up the assertion checking

No functionality changes.

llvm-svn: 11036

* Turn a bunch of instance variables into automatic variables

llvm-svn: 11035

Move Passes.h (which defines the interface to this file) to the top.
Move statistics to the top of the file.
Add a comment

llvm-svn: 11034

any test cases :-)

llvm-svn: 11032

of a linear search to find the first range for comparisons. This cuts
down the linear scan register allocator running time by a factor of 3
in 254.perlbmk and by a factor of 2.2 in 176.gcc.

llvm-svn: 11030

llvm-svn: 11029

Simplification of LiveIntervals::Interval::overlaps() and addition of
examples to overlaps() and liveAt() to make them clearer.

llvm-svn: 11028

Implement LiveVariables::getIndexMachineBasicBlock

llvm-svn: 11018

choose an ostream.

llvm-svn: 11016

when joining we need to check if we overlap with the second interval
or any of its aliases.

Also make joining intervals the default.

llvm-svn: 10973

is a move between two registers, at least one of the registers is
virtual and the two live intervals do not overlap.

This results in about 40% reduction in intervals, 30% decrease in the
register allocators running time and a 20% increase in peephole
optimizations (mainly move eliminations).

The option can be enabled by passing -join-liveintervals where
appropriate.

llvm-svn: 10965

with the current one.

llvm-svn: 10959

virtReg lives on the stack. Now a virtual register has an entry in the
virtual->physical map or the virtual->stack slot map but never in
both.

llvm-svn: 10958

llvm-svn: 10957

llvm-svn: 10956

llvm-svn: 10926