If the source of a move is in spill slot, the reload may be folded to essentially a load from stack slot. It's ok to mark the stack slot value as available for reuse. But it should not be clobbered since the destination of the move is live.

llvm-svn: 41109

hard to catch bugs with retaddr lowering

llvm-svn: 41104

llvm-svn: 41103

llvm-svn: 41096

Use dominance frontier to fixup incoming edges of successor blocks not domianted by DeadBB.
Use df_iterator to walk and delete basic blocks dominated by DeadBB.

llvm-svn: 41095

llvm-svn: 41094

llvm-svn: 41093

llvm-svn: 41091

llvm-svn: 41090

- If the defs of a spilled rematerializable MI are dead after the spill store is deleted, delete
  the def MI as well.

llvm-svn: 41086

Fix for PR1596: AdjustCopiesBackFrom() should conservatively check if any of its sub-registers may overlap with the interval of the copy that's being coalesced.

llvm-svn: 41084

If a MI's def is remat as well as spilled, and the store is later deemed dead, mark the def operand as isDead.

llvm-svn: 41083

llvm-svn: 41082

they're not related to eliminating a load.

llvm-svn: 41081

llvm-svn: 41080

llvm-svn: 41078

the function.

llvm-svn: 41077

llvm-svn: 41075

no more uses within the MBB and the spilled value isn't live out of the MBB.
Then it's safe to delete the spill store.

llvm-svn: 41069

spilled value is available for reuse.

llvm-svn: 41067

llvm-svn: 41064

llvm-svn: 41063

llvm-svn: 41062

Re-implement trivial rematerialization. This allows def MIs whose live intervals that are coalesced to be rematerialized.

llvm-svn: 41060

llvm-svn: 41059

llvm-svn: 41054

llvm-svn: 41053

llvm-svn: 41052

llvm-svn: 41051

llvm-svn: 41050

see if the base register is already occupied before assuming it can be
used. This fixes bogus code generation in the accompanying testcase.

llvm-svn: 41049

llvm-svn: 41048

Into: inttoptr (i64 0 to i8*)  -> null

This occurs in the example in PR1602.  With this fixed, we now compile
the example in PR1602 into fully "devirtualized" code:

define void @_Z1g1S(%struct.S* noalias  %s) {
entry:        %tmp131415 = getelementptr %struct.S* %s, i32 0, i32 0          ; <i32 (...)***> [#uses=1]        %tmp16 = load i32 (...)*** %tmp131415, align 4          ; <i32 (...)**> [#uses=1]
        %tmp26277 = load i32 (...)** %tmp16             ; <i32 (...)*> [#uses=1]
        %tmp2829 = bitcast i32 (...)* %tmp26277 to void (%struct.S*)*           ; <void (%struct.S*)*> [#uses=1]
        tail call void %tmp2829( %struct.S* %s )
        ret void
}

This still has the vtable dispatch (as required) but does not have any pointer
to method cruft left.

llvm-svn: 41046

llvm-svn: 41043

llvm-svn: 41029

llvm-svn: 41028

llvm-svn: 41024

us to fold the entry block of PR1602 to false instead of:

br i1 icmp eq (i32 and (i32 ptrtoint (void (%struct.S*)* inttoptr (i64
1 to void (%struct.S*)*) to i32), i32 1), i32 0), label %cond_next, label
%cond_true

llvm-svn: 41023

have complex pointer manipulation going on.  This allows us to compile
stuff like this:

__m128i foo(__m128i x){
                static const unsigned int c_0[4] = { 0, 0, 0, 0 };
                __m128i v_Zero = _mm_loadu_si128((__m128i*)c_0);
                x  = _mm_unpacklo_epi8(x,  v_Zero);
                return x;
}

into:

_foo:
        xorps   %xmm1, %xmm1
        punpcklbw       %xmm1, %xmm0
        ret

llvm-svn: 41022

llvm-svn: 41021