Yes, if the redef is a copy, update the old val# with the copy. But make sure to clear the copy field if the redef is not a copy.

llvm-svn: 103922

The implementation in LegalizeIntegerTypes to handle this as 
sint64->float + appropriate power of 2 is subject to double rounding,
considered incorrect by numerics people.  Use this implementation only
when it is safe.  This leads to using library calls in some cases
that produced inline code before, but it's correct now.
(EVTToAPFloatSemantics belongs somewhere else, any suggestions?)

Add a correctly rounding (though not particularly fast) conversion
that uses X87 80-bit computations for x86-32.

7885399, 5901940.  This shows up in gcc.c-torture/execute/ieee/rbug.c
in the gcc testsuite on some platforms.

llvm-svn: 103883

llvm-svn: 103882

patch by Evzen Muller!

llvm-svn: 103876

a condition's grouping. Every other use of Allocatable.test(Hint) groups it the
same way as it is indented, so move the parentheses to agree with that
grouping.

llvm-svn: 103869

When working top-down in a basic block, substituting physregs for virtregs, the use-def chains are kept up to date. That means we can recognize a virtreg kill by the use-def chain becoming empty.

This makes the fast allocator independent of incoming kill flags.

llvm-svn: 103866

llvm-svn: 103850

instructions.

e.g.
%reg1026<def> = VLDMQ %reg1025<kill>, 260, pred:14, pred:%reg0
%reg1027<def> = EXTRACT_SUBREG %reg1026, 6
%reg1028<def> = EXTRACT_SUBREG %reg1026<kill>, 5
...
%reg1029<def> = REG_SEQUENCE %reg1028<kill>, 5, %reg1027<kill>, 6, %reg1028, 7, %reg1027, 8, %reg1028, 9, %reg1027, 10, %reg1030<kill>, 11, %reg1032<kill>, 12

After REG_SEQUENCE is eliminated, we are left with:

%reg1026<def> = VLDMQ %reg1025<kill>, 260, pred:14, pred:%reg0
%reg1029:6<def> = EXTRACT_SUBREG %reg1026, 6
%reg1029:5<def> = EXTRACT_SUBREG %reg1026<kill>, 5

The regular coalescer will not be able to coalesce reg1026 and reg1029 because it doesn't
know how to combine sub-register indices 5 and 6. Now 2-address pass will consult the
target whether sub-registers 5 and 6 of reg1026 can be combined to into a larger
sub-register (or combined to be reg1026 itself as is the case here). If it is possible, 
it will be able to replace references of reg1026 with reg1029 + the larger sub-register
index.

llvm-svn: 103835

setting kill flags.

llvm-svn: 103832

llvm-svn: 103831

llvm-svn: 103830

llvm-svn: 103828

llvm-svn: 103827

llvm-svn: 103823

llvm-svn: 103822

llvm-svn: 103821

llvm-svn: 103820

llvm-svn: 103807

llvm-svn: 103806

while debugging what's mishandled about them in the post-RA pass.

llvm-svn: 103805

the variable actually tracks.

N.B., several back-ends are using "HasCalls" as being synonymous for something
that adjusts the stack. This isn't 100% correct and should be looked into.

llvm-svn: 103802

llvm-svn: 103798

- Kill is implicit when use and def registers are identical.
- Only virtual registers can differ.

Add a -verify-fast-regalloc to run the verifier before the fast allocator.

llvm-svn: 103797

This adds extra security against using clobbered physregs, and it adds kill
markers to physreg uses.

llvm-svn: 103784

-filetype=obj test, and -filetype=obj leaks a few objects. Added a FIXME, we
need to sort out the ownership model for the various MC objects.

llvm-svn: 103769

 - This is a hack, but I can't decide the best place to handle this. Chris?

llvm-svn: 103765

llvm-svn: 103764

llvm-svn: 103748

This loop is quadratic in the capacity for a DenseMap:

  while(!map.empty())
    map.erase(map.begin());

Instead we now do a normal begin() - end() iteration followed by map.clear().
That also has the nice sideeffect of shrinking the map capacity on demand.

llvm-svn: 103747

one was subject to double rounding in extreme cases.

llvm-svn: 103744

llvm-svn: 103739

when they move instructions.

llvm-svn: 103737

use of it in MachineCSE.

llvm-svn: 103726

basic block.

llvm-svn: 103725

This causes way more identity copies to be generated, ripe for coalescing.

llvm-svn: 103686

llvm-svn: 103685

If REG_SEQUENCE source is livein, copy it first. Also, update livevariables information when a copy is introduced.

llvm-svn: 103680

llvm-svn: 103679

The X86 floating point stack pass and others depend on good kill flags.

llvm-svn: 103635

llvm-svn: 103586