2. Rewrite operator=(const APInt& RHS) to allow the RHS to be a different
   bit width than the LHS. This makes it possible to use APInt as the key
   of a DenseMap, as needed for the IntConstants map in Constants.cpp
3. Fix operator=(uint64_t) to clear unused bits in case the client assigns
   a value that has more bits than the APInt allows.
4. Assert that bit widths are equal in operator==
5. Revise getHashValue() to put the bit width in the low order six bits.
   This should help to make i1 0, i2 0, ... i64 0 all distinct in the
   IntConstants DenseMap.

llvm-svn: 34646

llvm-svn: 34645

llvm-svn: 34643

Fix toString use of getValue to use getZExtValue()

llvm-svn: 34642

   ConstantInt better.
2. Add a getHashValue() method.

llvm-svn: 34641

llvm-svn: 34640

llvm-svn: 34639

llvm-svn: 34638

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