tail merging support to handle more cases.
- Recognize several cases where tail merging is beneficial even when
the tail size is smaller than the generic threshold.
- Make use of MachineInstrDesc::isBarrier to help detect
non-fallthrough blocks.
- Check for and avoid disrupting fall-through edges in more cases.
llvm-svn: 86871
llvm.invariant.start to be used without necessarily being paired with a call
to llvm.invariant.end. If you run the entire optimization pipeline then such
calls are in fact deleted (adce does it), but that's actually a good thing since
we probably do want them to be zapped late in the game. There should really be
an integration test that checks that the llvm.invariant.start call lasts long
enough that all passes that do interesting things with it get to do their stuff
before it is deleted. But since no passes do anything interesting with it yet
this will have to wait for later.
llvm-svn: 86840
constant whose component type is not a legal type for the target.
(If the target ConstantPool cannot handle this type either, it has
an opportunity to merge elements. In practice any target with
8-bit bytes must support i8 *as data*). 7320806 (partial).
llvm-svn: 86751
generates a sequence similar to this:
__Z4funci:
LFB2:
mflr r0
LCFI0:
stmw r30,-8(r1)
LCFI1:
stw r0,8(r1)
LCFI2:
stwu r1,-80(r1)
LCFI3:
mr r30,r1
LCFI4:
where LCFI3 and LCFI4 are used by the FDE to indicate what the FP, LR, and other
things are. We generated something more like this:
Leh_func_begin1:
mflr r0
stw r31, 20(r1)
stw r0, 8(r1)
Llabel1:
stwu r1, -80(r1)
Llabel2:
mr r31, r1
Note that we are missing the "mr" instruction. This patch makes it more like the
GCC output.
llvm-svn: 86729
debug intrinsics, and an unconditional branch when possible. This
reuses the TryToSimplifyUncondBranchFromEmptyBlock function split
out of simplifycfg.
llvm-svn: 86722
just one level deep. On the testcase we go from getting this:
F1: ; preds = %T2
%F = and i1 true, %cond ; <i1> [#uses=1]
br i1 %F, label %X, label %Y
to a fully threaded:
F1: ; preds = %T2
br label %Y
This changes gets us to the point where we're forming (too many) switch
instructions on doug's strswitch testcase.
llvm-svn: 86646
the loop. This is needed because with indirectbr it may not be possible
for LoopSimplify to guarantee that all loop exit predecessors are
inside the loop. This fixes PR5437.
LCCSA no longer actually requires LoopSimplify form, but for now it
must still have the dependency because the PassManager doesn't know
how to schedule LoopSimplify otherwise.
llvm-svn: 86569
here:
1) We need to avoid processing sigma nodes as phi nodes for constraint generation.
2) We need to generate constraints for comparisons against constants properly.
This includes our first working ABCD test!
llvm-svn: 86498
when both the source and dest are illegal types, since it would cause
the phi to grow (for example, we shouldn't transform test14b's phi to
a phi on i320). This fixes an infinite loop on i686 bootstrap with
phi slicing turned on, so turn it back on.
llvm-svn: 86483
Also, fix a few other details of the cmake test target and rename it to
'check'. CMake tests now work for the most part, but there are a handful of
failures left due to missing site.exp bits.
llvm-svn: 86452
Dan Gohman