first is a correctness thing, and the later is an optzn thing. This also
is needed to support a future change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22720 91177308-0d34-0410-b5e6-96231b3b80d8
Includes wider support for rotate and mask cases.
Patch by Jim Laskey.
I've requested that Jim add new regression tests the newly handled cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22712 91177308-0d34-0410-b5e6-96231b3b80d8
The termination condition actually wants to use the post-incremented value
of the loop, not a new indvar with an unusual base.
On PPC, for example, this allows us to compile
LoopStrengthReduce/exit_compare_live_range.ll to:
_foo:
li r2, 0
.LBB_foo_1: ; no_exit
li r5, 0
stw r5, 0(r3)
addi r2, r2, 1
cmpw cr0, r2, r4
bne .LBB_foo_1 ; no_exit
blr
instead of:
_foo:
li r2, 1 ;; IV starts at 1, not 0
.LBB_foo_1: ; no_exit
li r5, 0
stw r5, 0(r3)
addi r5, r2, 1
cmpw cr0, r2, r4
or r2, r5, r5 ;; Reg-reg copy, extra live range
bne .LBB_foo_1 ; no_exit
blr
This implements LoopStrengthReduce/exit_compare_live_range.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22699 91177308-0d34-0410-b5e6-96231b3b80d8
* Teach this code to move allocas out of the loop when tail call eliminating
a call marked 'tail'. This implements TailCallElim/move_alloca_for_tail_call.ll
* Do not perform this transformation if a call is marked 'tail' and if there
are allocas that we cannot move out of the loop in #2. Doing so would increase
the stack usage of the function. This implements fixes
PR615 and TailCallElim/dont-tce-tail-marked-call.ll.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22690 91177308-0d34-0410-b5e6-96231b3b80d8
depending on the command line option. Now the command line option just
sets the subtarget as appropriate. G5 opts will now default to on on
G5-enabled nightly testers among other machines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22688 91177308-0d34-0410-b5e6-96231b3b80d8
to pass it in. Also, since it always returns a non-null pointer, make it
return a reference instead for easier use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22686 91177308-0d34-0410-b5e6-96231b3b80d8
avoid revisiting nodes more than once. This eliminates a source of
potentially exponential behavior. For a small function in 191.fma3d
(hexah_stress_divergence_), this speeds up isel from taking > 20mins to
taking 0.07s.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22680 91177308-0d34-0410-b5e6-96231b3b80d8