return value as a whole in deadargelim is really not needed now that we simply
rebuild the old return value and actually prevents some canonicalization from
taking place.
This revert stops deadargelim from changing {i32} into i32 for now, but I'll
fix that next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53609 91177308-0d34-0410-b5e6-96231b3b80d8
return values that are still (partially) live. Instead of updating all uses of
a call instruction after removing some elements, it now just rebuilds the
original struct (With undef gaps where the unused values were) and leaves it to
instcombine to clean this up.
The added testcase still fails currently, but this is due to instcombine which
isn't good enough yet. I will fix that part next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53608 91177308-0d34-0410-b5e6-96231b3b80d8
only the liveness of partial return values (for functions returning a struct).
This is more explicit to prevent unwanted changes in the return value.
In particular, deadargelim now canonicalizes a function returning {i32} to
returning i32 and {} to void, if the struct returned is not used in its
entirety, but only the single element is used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53606 91177308-0d34-0410-b5e6-96231b3b80d8
and return values live for those functions. This doesn't change anything yet,
but prepares for the coming commits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53601 91177308-0d34-0410-b5e6-96231b3b80d8
the min/max values for an integer type, compare against the min/max
values we can prove contain the input. This might be a tighter bound,
so this is general goodness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53446 91177308-0d34-0410-b5e6-96231b3b80d8
was using the algorithm for folding unsigned comparisons which is
completely wrong. This has been broken since the signless types change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53444 91177308-0d34-0410-b5e6-96231b3b80d8
This cause a regression in InstCombine/JavaCompare, which was doing the right
thing on accident. To handle the missed case, generalize the comparisons based
on masked bits a little bit to handle comparisons against the max value. For
example, we can now xform (slt i32 (and X, 4), 4) -> (setne i32 (and X, 4), 4)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53443 91177308-0d34-0410-b5e6-96231b3b80d8
Rewrite the DeadArgumentElimination pass, to use a more explicit tracking of
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.
The pass now looks properly inside returned structs, but only at the first
level (ie, not inside nested structs).
This version fixed a few more bugs and was cleaned up a bit. It now passes all
of LLVM's testing, and should still pass SPEC2006. There is still a minor bug
with regard to returning nested structs. Since there is currently nothing that
emits such IR, I will fix that in a seperate commit (partly because it requires
a non-trivial fix).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53400 91177308-0d34-0410-b5e6-96231b3b80d8
into phis. This is actually the same bug as PR2262 /
2008-04-29-VolatileLoadDontMerge.ll, but I missed checking the first
predecessor for multiple successors. Testcase here:
InstCombine/2008-07-08-VolatileLoadMerge.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53240 91177308-0d34-0410-b5e6-96231b3b80d8
1. LSR runOnLoop is always returning false regardless if any transformation is made.
2. AddUsersIfInteresting can create new instructions that are added to DeadInsts. But there is a later early exit which prevents them from being freed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53193 91177308-0d34-0410-b5e6-96231b3b80d8
