LCSSA is still the slowest pass when gccas'ing 252.eon, but now it only takes
39s instead of 289s. :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28776 91177308-0d34-0410-b5e6-96231b3b80d8
not handling PHI nodes correctly when determining if a value was live-out.
This patch reduces the number of detected live-out variables in the testcase
from 6565 to 485.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28771 91177308-0d34-0410-b5e6-96231b3b80d8
If a single exit block has multiple predecessors within the loop, it will
appear in the exit blocks list more than once. LCSSA needs to take that into
account so that it doesn't double process that exit block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28750 91177308-0d34-0410-b5e6-96231b3b80d8
to link in the implementation. Thanks to Anton Korobeynikov for figuring out
what was going on here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28660 91177308-0d34-0410-b5e6-96231b3b80d8
code (while cloning) it often gets the branch/switch instructions. Since it
knows that edges of the CFG are dead, it need not clone (or even look) at
the obviously dead blocks. This should speed up the inliner substantially on
code where there are lots of inlinable calls to functions with constant
arguments. On C++ code in particular, this kicks in.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28641 91177308-0d34-0410-b5e6-96231b3b80d8
reimplement getValueDominatingFunction to walk the DominanceTree rather than
just searching blindly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28618 91177308-0d34-0410-b5e6-96231b3b80d8
is now theoretically feature-complete. It has not, however, been thoroughly
test, and is still considered experimental.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28529 91177308-0d34-0410-b5e6-96231b3b80d8
the iterated Dominance Frontier of the loop-closure Phi's. This is the
second phase of the LCSSA pass. The third phase (coming soon) will be to
update all uses of loop variables to use the loop-closure Phi's instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28524 91177308-0d34-0410-b5e6-96231b3b80d8
makes it so that it constant folds instructions on the fly. This is good
for several reasons:
0. Many instructions are constant foldable after inlining, particularly if
inlining a call with constant arguments.
1. Without this, the inliner has to allocate memory for all of the instructions
that can be constant folded, then a subsequent pass has to delete them. This
gets the job done without this extra work.
2. This makes the inliner *pass* a bit more aggressive: in particular, it
partially solves a phase order issue where the inliner would inline lots
of code that folds away to nothing, but think that the resultant function
is big because of this code that will be gone. Now the code never exists.
This is the first part of a 2-step process. The second part will be smart
enough to see when this implicit constant folding propagates a constant into
a branch or switch instruction, making CFG edges dead.
This implements Transforms/Inline/inline_constprop.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28521 91177308-0d34-0410-b5e6-96231b3b80d8
nondeterminism being bad) could cause some trivial missed optimizations (dead
phi nodes being left around for later passes to clean up).
With this, llvm-gcc4 now bootstraps and correctly compares. I don't know
why I never tried to do it before... :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27984 91177308-0d34-0410-b5e6-96231b3b80d8
