When a new phi is generated for scalarpre of an expression, the phiTranslate cache
will become stale: Before PRE, the candidate expression must not be available in a
predecessor block, and phitranslate will cache the information. After PRE, the
expression will become available in all predecessor blocks, so the related entries
in phiTranslate cache becomes stale. The patch will simply remove the stale entries
so phiTranslate can be recomputed next time.
The stale entries in phitranslate cache will not affect correctness but will cause
missing PRE opportunity for later instructions.
Differential Revision: https://reviews.llvm.org/D36124
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310421 91177308-0d34-0410-b5e6-96231b3b80d8
Recommit after workaround the bug PR31652.
Three bugs fixed in previous recommits: The first one is to use CurrentBlock
instead of PREInstr's Parent as param of performScalarPREInsertion because
the Parent of a clone instruction may be uninitialized. The second one is stop
PRE when CurrentBlock to its predecessor is a backedge and an operand of CurInst
is defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available. The third one is an out-of-bound
array access in a flipped if guard.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309397 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Currently, when GVN creates a load and when InstCombine creates a new store for unreachable Load, the DebugLoc info gets lost.
Reviewers: dberlin, davide, aprantl
Reviewed By: aprantl
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D34639
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308404 91177308-0d34-0410-b5e6-96231b3b80d8
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307722 91177308-0d34-0410-b5e6-96231b3b80d8
Going through the Constant methods requires redetermining that the Constant is a ConstantInt and then calling isZero/isOne/isMinusOne.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307292 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r306313. This breaks selfhost at -O3 and PR33652.
Let me know if you need additional information on reproducing the issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307021 91177308-0d34-0410-b5e6-96231b3b80d8
The recommit fixes three bugs: The first one is to use CurrentBlock instead of
PREInstr's Parent as param of performScalarPREInsertion because the Parent
of a clone instruction may be uninitialized. The second one is stop PRE when
CurrentBlock to its predecessor is a backedge and an operand of CurInst is
defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available. The third one is an out-of-bound
array access in a flipped if guard.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306313 91177308-0d34-0410-b5e6-96231b3b80d8
The recommit fixes two bugs: The first one is to use CurrentBlock instead of
PREInstr's Parent as param of performScalarPREInsertion because the Parent
of a clone instruction may be uninitialized. The second one is stop PRE when
CurrentBlock to its predecessor is a backedge and an operand of CurInst is
defined inside of CurrentBlock. The same value defined inside of loop in last
iteration can not be regarded as available.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305578 91177308-0d34-0410-b5e6-96231b3b80d8
The recommit is to fix a bug about ExtractValue and InsertValue ops. For those
ops, some varargs inside GVN::Expression are not value numbers but raw index
numbers. It is wrong to do phi-translate for raw index numbers, and the fix is
to stop doing that.
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304050 91177308-0d34-0410-b5e6-96231b3b80d8
Right now scalarpre doesn't have phi-translate support, so it will miss some
simple pre opportunities. Like the following testcase, current scalarpre cannot
recognize the last "a * b" is fully redundent because a and b used by the last
"a * b" expr are both defined by phis.
long a[100], b[100], g1, g2, g3;
__attribute__((pure)) long goo();
void foo(long a, long b, long c, long d) {
g1 = a * b;
if (__builtin_expect(g2 > 3, 0)) {
a = c;
b = d;
g2 = a * b;
}
g3 = a * b; // fully redundant.
}
The patch adds phi-translate support in scalarpre. This is only a temporary
solution before the newpre based on newgvn is available.
Differential Revision: https://reviews.llvm.org/D32252
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303923 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Implements PR889
Removing the virtual table pointer from Value saves 1% of RSS when doing
LTO of llc on Linux. The impact on time was positive, but too noisy to
conclusively say that performance improved. Here is a link to the
spreadsheet with the original data:
https://docs.google.com/spreadsheets/d/1F4FHir0qYnV0MEp2sYYp_BuvnJgWlWPhWOwZ6LbW7W4/edit?usp=sharing
This change makes it invalid to directly delete a Value, User, or
Instruction pointer. Instead, such code can be rewritten to a null check
and a call Value::deleteValue(). Value objects tend to have their
lifetimes managed through iplist, so for the most part, this isn't a big
deal. However, there are some places where LLVM deletes values, and
those places had to be migrated to deleteValue. I have also created
llvm::unique_value, which has a custom deleter, so it can be used in
place of std::unique_ptr<Value>.
I had to add the "DerivedUser" Deleter escape hatch for MemorySSA, which
derives from User outside of lib/IR. Code in IR cannot include MemorySSA
headers or call the MemoryAccess object destructors without introducing
a circular dependency, so we need some level of indirection.
Unfortunately, no class derived from User may have any virtual methods,
because adding a virtual method would break User::getHungOffOperands(),
which assumes that it can find the use list immediately prior to the
User object. I've added a static_assert to the appropriate OperandTraits
templates to help people avoid this trap.
Reviewers: chandlerc, mehdi_amini, pete, dberlin, george.burgess.iv
Reviewed By: chandlerc
Subscribers: krytarowski, eraman, george.burgess.iv, mzolotukhin, Prazek, nlewycky, hans, inglorion, pcc, tejohnson, dberlin, llvm-commits
Differential Revision: https://reviews.llvm.org/D31261
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303362 91177308-0d34-0410-b5e6-96231b3b80d8
and to expose a handle to represent the actual case rather than having
the iterator return a reference to itself.
All of this allows the iterator to be used with common STL facilities,
standard algorithms, etc.
Doing this exposed some missing facilities in the iterator facade that
I've fixed and required some work to the actual iterator to fully
support the necessary API.
Differential Revision: https://reviews.llvm.org/D31548
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300032 91177308-0d34-0410-b5e6-96231b3b80d8
NFCI.
Summary:
This is ground work for the changes to enable coercion in NewGVN.
GVN doesn't care if they end up constant because it eliminates as it goes.
NewGVN cares.
IRBuilder and ConstantFolder deliberately present the same interface,
so we use this to our advantage to templatize our functions to make
them either constant only or not.
Reviewers: davide
Subscribers: llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D30928
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298262 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
iterateOnFunction creates a ReversePostOrderTraversal object which does a post order traversal in its constructor and stores the results in an internal vector. Iteration over it just reads from the internal vector in reverse order.
The GVN code seems to be unaware of this and iterates over ReversePostOrderTraversal object and makes a copy of the vector into a local vector. (I think at one point in time we used a DFS here instead which would have required the local vector).
The net affect of this is that we have two vectors containing the basic block list. As I didn't want to expose the implementation detail of ReversePostOrderTraversal's constructor to GVN, I've changed the code to do an explicit post order traversal storing into the local vector and then reverse iterate over that.
I've also removed the reserve(256) since the ReversePostOrderTraversal wasn't doing that. I can add it back if we thinks it important. Though it seemed weird that it wasn't based on the size of the function.
Reviewers: davide, anemet, dberlin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31084
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298191 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
These are the functions used to determine when values of loads can be
extracted from stores, etc, and to perform the necessary insertions to
do this. There are no changes to the functions themselves except
reformatting, and one case where memdep was informed of a removed load
(which was pushed into the caller).
Reviewers: davide
Subscribers: mgorny, llvm-commits, Prazek
Differential Revision: https://reviews.llvm.org/D30478
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297438 91177308-0d34-0410-b5e6-96231b3b80d8
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html
For reference:
- Public headers should just declare the dump() method but not use
LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MyClass::dump() {
// print stuff to dbgs()...
}
#endif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293359 91177308-0d34-0410-b5e6-96231b3b80d8
After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is more computationally efficient, and also we need much less
code...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289756 91177308-0d34-0410-b5e6-96231b3b80d8
In the case of a fully redundant load LI dominated by an equivalent load V, GVN
should always preserve the original debug location of V. Otherwise, we risk to
introduce an incorrect stepping.
If V has debug info, then clearly it should not be modified. If V has a null
debugloc, then it is still potentially incorrect to propagate LI's debugloc
because LI may not post-dominate V.
Differential Revision: https://reviews.llvm.org/D27468
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288903 91177308-0d34-0410-b5e6-96231b3b80d8
If LoopInfo is available during GVN, BasicAA will use it. However
MergeBlockIntoPredecessor does not update LI as it merges blocks.
This didn't use to cause problems because LI was freed before
GVN/BasicAA. Now with OptimizationRemarkEmitter, the lifetime of LI is
extended so LI needs to be kept up-to-date during GVN.
Differential Revision: https://reviews.llvm.org/D27288
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288307 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r288046.
Trying to see if the revert fixes a compiler crash during a stage2 LTO
build with a GVN backtrace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288179 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r288047.
Trying to see if the revert fixes a compiler crash during a stage2 LTO
build with a GVN backtrace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288178 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r288090.
Trying to see if the revert fixes a compiler crash during a stage2 LTO
build with a GVN backtrace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288177 91177308-0d34-0410-b5e6-96231b3b80d8
There's no agreement about this patch. I personally find the
PRE machinery of the current GVN hard enough to reason about
that I'm not sure I'll try to land this again, instead of working
on the rewrite).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284796 91177308-0d34-0410-b5e6-96231b3b80d8
In theory this could be generalized to move anything where
we prove the operands are available, but that would require
rewriting PRE. As NewGVN will hopefully come soon, and we're
trying to rewrite PRE in terms of NewGVN+MemorySSA, it's probably
not worth spending too much time on it. Fix provided by
Daniel Berlin!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284311 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor replaceDominatedUsesWith to have a flag to control whether to replace uses in BB itself.
Summary: This is in preparation for LoopSink pass which calls replaceDominatedUsesWith to update after sinking.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280949 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This is in preparation for LoopSink pass which calls replaceDominatedUsesWith to update after sinking.
Reviewers: chandlerc, davidxl, danielcdh
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24170
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280427 91177308-0d34-0410-b5e6-96231b3b80d8
Besides a general consistently benefit, the extra layer of indirection
allows the mechanical part of https://reviews.llvm.org/D23256 that
requires touching every transformation and analysis to be factored out
cleanly.
Thanks to David for the suggestion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278077 91177308-0d34-0410-b5e6-96231b3b80d8
