llvm-svn: 34637

conventions.  This doesn't do anything yet, but may in the future.

llvm-svn: 34636

easier to comprehend and might be useful elsewhere.

llvm-svn: 34635

llvm-svn: 34634

llvm-svn: 34633

llvm-svn: 34632

mechanics that process it.  I'm still not happy with this, but it's a step
in the right direction.

llvm-svn: 34631

llvm-svn: 34630

2. Fix countTrailingZeros to use a faster algorithm.
3. Simplify sext() slightly by using isNegative().
4. Implement ashr using word-at-a-time logic instead of bit-at-a-time
5. Rename locals named isNegative so they don't clash with method name.
6. Fix fromString to compute negated value correctly.

llvm-svn: 34629

llvm-svn: 34628

llvm-svn: 34627

llvm-svn: 34626

llvm-svn: 34625

llvm-svn: 34624

Capture this so that downstream zext/sext's are optimized out.  This
compiles:
  int test(short X) { return (int)X; }

to:

_test:
        movl %edi, %eax
        ret

instead of:

_test:
        movswl %di, %eax
        ret


GCC produces this bizarre code:

_test:
        movw    %di, -12(%rsp)
        movswl  -12(%rsp),%eax
        ret

llvm-svn: 34623

llvm-svn: 34622

sextinreg if not needed.   This is useful in two cases: before legalize,
it avoids creating a sextinreg that will be trivially removed.  After legalize
if the target doesn't support sextinreg, the trunc/sext would not have been
removed before.

llvm-svn: 34621

llvm-svn: 34620

This is much less expensive than a test against zero.

llvm-svn: 34619

This makes it much more efficient.

llvm-svn: 34618

llvm-svn: 34617

2. Implement the trunc, sext, and zext operations.
3. Improve fromString to accept negative values as input.

llvm-svn: 34616

void foo(short);
void bar(unsigned short A) {
  foo(A);
}

into:

_bar:
        subq $8, %rsp
        movswl %di, %edi
        call _foo
        addq $8, %rsp
        ret

instead of:

_bar:
        subq $8, %rsp
        call _foo
        addq $8, %rsp
        ret

Testcase here: test/CodeGen/X86/x86-64-shortint.ll

llvm-svn: 34615

llvm-svn: 34614

night:  fastcc returns should only go in XMM0 if we have SSE2 or above.

llvm-svn: 34613

llvm-svn: 34612

llvm-svn: 34611

llvm-svn: 34610

llvm-svn: 34609

exprs hanging off a global, even if the global is not otherwise dead.  This
requires some tricky iterator gymnastics.

This implements Transforms/GlobalOpt/constantexpr-dangle.ll by deleting a
constantexpr that made it appear that the address of the function was taken.

llvm-svn: 34608

llvm-svn: 34607

llvm-svn: 34606

llvm-svn: 34605

llvm-svn: 34604

2. Move comments for methods to .h file, delete them in .cpp file.
3. All places that were doing manual clear of high order bits now call the
   clearUnusedBits() method in order to not depend on undefined behavior
   of the >> operator when the number of bits shifted equals the word size.
4. Reduced # of loc by using the new result of clearUnusedBits() method.
5. Simplified logic (decreased indentation) in a few places.
6. Added code comments to larger functions that needed them.
7. Added FIXME notes about weak implementations of things (e.g. bit-by-bit
   shift right is sub-optimal).

llvm-svn: 34603

when the bit size is equal to the word size. This happens to work out okay
on x86, but might not on other platforms. The change just detects when
there are no bits to clear (because BitWidth is a multiple of the word size)
and returns early.

Also, move some comments from .cpp file into header.

llvm-svn: 34602

external symbols and global addresses.  Add the missing ones.

one important workaround: PPCISD::CALL is matched by both PPCcall_ELF
and PPCcall_Macho, disable the _ELF patterns for now.

llvm-svn: 34601

llvm-svn: 34600

llvm-svn: 34599

llvm-svn: 34598