17 Commits

Author SHA1 Message Date
Nikita Popov
8979ae4276 [SimplifyCFG] Convert tests to opaque pointers (NFC) 2022-12-14 15:14:12 +01:00
Roman Lebedev
d1d1293569
[NFC] Port all runlines for SimplifyCFG pass tests to -passes syntax 2022-12-05 21:12:20 +03:00
Roman Lebedev
371fcb720e
[SimplifyCFG][PhaseOrdering] Defer lowering switch into an integer range comparison and branch until after at least the IPSCCP
That transformation is lossy, as discussed in
https://github.com/llvm/llvm-project/issues/53853
and https://github.com/rust-lang/rust/issues/85133#issuecomment-904185574

This is an alternative to D119839,
which would add a limited IPSCCP into SimplifyCFG.

Unlike lowering switch to lookup, we still want this transformation
to happen relatively early, but after giving a chance for the things
like CVP to do their thing. It seems like deferring it just until
the IPSCCP is enough for the tests at hand, but perhaps we need to
be more aggressive and disable it until CVP.

Fixes https://github.com/llvm/llvm-project/issues/53853
Refs. https://github.com/rust-lang/rust/issues/85133

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D119854
2022-02-17 12:13:55 +03:00
Roman Lebedev
3e98b88797
[NFC][SimplifyCFG] Fix tests to use FileCheck instead of grep 2021-06-21 23:56:54 +03:00
Roman Lebedev
5cce4aff18
[SimplifyCFG] TryToSimplifyUncondBranchFromEmptyBlock() already knows how to preserve DomTree
... so just ensure that we pass DomTreeUpdater it into it.

Fixes DomTree preservation for a large number of tests,
all of which are marked as such so that they do not regress.
2020-12-17 01:03:49 +03:00
Eric Christopher
cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher
a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Hyojin Sung
4673f10568 [SimlifyCFG] Prevent passes from destroying canonical loop structure, especially for nested loops
When eliminating or merging almost empty basic blocks, the existence of non-trivial PHI nodes
is currently used to recognize potential loops of which the block is the header and keep the block.
However, the current algorithm fails if the loops' exit condition is evaluated only with volatile
values hence no PHI nodes in the header. Especially when such a loop is an outer loop of a nested
loop, the loop is collapsed into a single loop which prevent later optimizations from being
applied (e.g., transforming nested loops into simplified forms and loop vectorization).
    
The patch augments the existing PHI node-based check by adding a pre-test if the BB actually
belongs to a set of loop headers and not eliminating it if yes.

llvm-svn: 264697
2016-03-29 04:08:57 +00:00
Reid Kleckner
ba85781f58 Revert "[SimlifyCFG] Prevent passes from destroying canonical loop structure, especially for nested loops"
This reverts commit r264596.

It does not compile.

llvm-svn: 264604
2016-03-28 18:07:40 +00:00
Hyojin Sung
0ada5b0d14 [SimlifyCFG] Prevent passes from destroying canonical loop structure, especially for nested loops
When eliminating or merging almost empty basic blocks, the existence of non-trivial PHI nodes
is currently used to recognize potential loops of which the block is the header and keep the block.
However, the current algorithm fails if the loops' exit condition is evaluated only with volatile
values hence no PHI nodes in the header. Especially when such a loop is an outer loop of a nested
loop, the loop is collapsed into a single loop which prevent later optimizations from being 
applied (e.g., transforming nested loops into simplified forms and loop vectorization).

The patch augments the existing PHI node-based check by adding a pre-test if the BB actually 
belongs to a set of loop headers and not eliminating it if yes. 

llvm-svn: 264596
2016-03-28 17:22:25 +00:00
Duncan Sands
e773c08021 TryToSimplifyUncondBranchFromEmptyBlock was checking that any common
predecessors of the two blocks it is attempting to merge supply the
same incoming values to any phi in the successor block.  This change
allows merging in the case where there is one or more incoming values
that are undef.  The undef values are rewritten to match the non-undef
value that flows from the other edge.  Patch by Mark Lacey.

llvm-svn: 186069
2013-07-11 08:28:20 +00:00
Dan Gohman
1880092722 Change tests from "opt %s" to "opt < %s" so that opt doesn't see the
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.

llvm-svn: 81537
2009-09-11 18:01:28 +00:00
Dan Gohman
72a13d2476 Use opt -S instead of piping bitcode output through llvm-dis.
llvm-svn: 81257
2009-09-08 22:34:10 +00:00
Dan Gohman
9737a63ed8 Change these tests to feed the assembly files to opt directly, instead
of using llvm-as, now that opt supports this.

llvm-svn: 81226
2009-09-08 16:50:01 +00:00
Tanya Lattner
baa370b37a Upgrade tests to not use llvm-upgrade.
llvm-svn: 48483
2008-03-18 03:45:45 +00:00
Reid Spencer
a551c041f9 For PR1319:
Upgrade to use new Tcl exec based test harness. This exposes 3 bugs that
were previously not being reported:
test/Transforms/GlobalDCE/2002-08-17-FunctionDGE.ll
test/Transforms/GlobalOpt/memset.ll
test/Transforms/IndVarsSimplify/exit_value_tests.llx

llvm-svn: 36065
2007-04-15 09:21:47 +00:00
Reid Spencer
83b3d82672 Regression is gone, don't try to find it on clean target.
llvm-svn: 33296
2007-01-17 07:59:14 +00:00