Add a new DenseMapInfo::isEqual method to allow clients to redefine
the equality predicate used when probing the hash table.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42042 91177308-0d34-0410-b5e6-96231b3b80d8
In the old way, we computed and inserted phi nodes for the whole IDF of
the definitions of the alloca, then computed which ones were dead and
removed them.
In the new method, we first compute the region where the value is live,
and use that information to only insert phi nodes that are live. This
eliminates the need to compute liveness later, and stops the algorithm
from inserting a bunch of phis which it then later removes.
This speeds up the testcase in PR1432 from 2.00s to 0.15s (14x) in a
release build and 6.84s->0.50s (14x) in a debug build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40825 91177308-0d34-0410-b5e6-96231b3b80d8
to the worklist, and handling the last one with a 'tail call'. This speeds
up PR1432 from 2.0578s to 2.0012s (2.8%)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40822 91177308-0d34-0410-b5e6-96231b3b80d8
faster than with the 'local to a block' fastpath. This speeds
up PR1432 from 2.1232 to 2.0686s (2.6%)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40818 91177308-0d34-0410-b5e6-96231b3b80d8
to increment NumLocalPromoted, and didn't actually delete the
dead alloca, leading to an extra iteration of mem2reg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40817 91177308-0d34-0410-b5e6-96231b3b80d8
stored value was a non-instruction value. Doh.
This increase the # single store allocas from 8982 to 9026, and
speeds up mem2reg on the testcase in PR1432 from 2.17 to 2.13s.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40813 91177308-0d34-0410-b5e6-96231b3b80d8
1. Check for revisiting a block before checking domination, which is faster.
2. If the stored value isn't an instruction, we don't have to check for domination.
3. If we have a value used in the same block more than once, make sure to remove the
block from the UsingBlocks vector. Not doing so forces us to go through the slow
path for the alloca.
The combination of these improvements increases the number of allocas on the fastpath
from 8935 to 8982 on PR1432. This speeds it up from 2.90s to 2.20s (31%)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40811 91177308-0d34-0410-b5e6-96231b3b80d8
a using block from the list if we handle it. Not doing this caused us
to not be able to promote (with the fast path) allocas which have uses (whoops).
This increases the # allocas hitting this fastpath from 4042 to 8935 on the
testcase in PR1432, speeding up mem2reg by 2.6x
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40809 91177308-0d34-0410-b5e6-96231b3b80d8
BBNumbers. Instead of using a bi-directional mapping, just use a single
densemap. This speeds up mem2reg on 176.gcc by 8%, from 1.3489 to
1.2485s.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33940 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... :)
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has a single def. In this case, look for uses that are dominated by the def
and attempt to rewrite them to directly use the stored value.
This speeds up mem2reg on these values and reduces the number of phi nodes
inserted. This should address PR665.
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BasicBlock's removePredecessor routine. This requires shuffling around
the definition and implementation of hasContantValue from Utils.h,cpp into
Instructions.h,cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22664 91177308-0d34-0410-b5e6-96231b3b80d8
The optimization for locally used allocas was not safe for allocas that
were read before they were written. This change disables that optimization
in that case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22318 91177308-0d34-0410-b5e6-96231b3b80d8
