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!
llvm-svn: 284311
BasicBlock::size is O(insts), making this loop O(blocks*insts), which
can be really slow on generated code. getPrevNode already checks if
we're at the beginning of the block and returns nullptr if so, just use
that instead. No functionality change intended.
llvm-svn: 284303
Instead of annotating (most of) the APInt API, we can just annotate
the type directly. This is less code and it will warn in more cases.
llvm-svn: 284297
This diff replaces manual parsing of the comma-separated list of names with
cl::list and cl::CommaSeparated.
Test plan: make -j8 check-clang-tools
Differential revision: https://reviews.llvm.org/D25586
llvm-svn: 284291
- Removed unused class members.
- Made class internal data private.
- Made class scoped data function scoped where it's possible.
- Replace naked new/delete with unique_ptr.
- Made resources guaranteed to be freed.
Differential Revision: https://reviews.llvm.org/D25464
llvm-svn: 284290
Although the itanium environment uses the itanium layout for C++, treat the
dllexport semantics more similarly to the MSVC specification. This preserves
the existing behaviour for the use of the itanium ABI on non-windows-itanium
environments. Export the inline definitions too.
llvm-svn: 284288
The previous names were both misleading (the MachineLegalizer actually
contained the info tables) and inconsistent with the selector & translator (in
having a "Machine") prefix. This should make everything sensible again.
The only functional change is the name of a couple of command-line options.
llvm-svn: 284287
This is essentially a more powerful version of our current
LLVM_ATTRIBUTE_UNUSED_RESULT, in that it can also be applied to types
and generate warnings whenever an object of that type is returned by
value and the value is discarded.
I'll replace uses of LLVM_ATTRIBUTE_UNUSED_RESULT and remove that
macro in follow up commits.
llvm-svn: 284286
1) Merge and demote variable definitions when we find a redefinition in
MergeVarDecls, not only when we find one in AddInitializerToDecl (we only reach
the second case if it's the addition of the initializer itself that converts an
existing declaration into a definition).
2) When rebuilding a redeclaration chain for a variable, if we merge two
definitions together, mark the definitions as merged so the retained definition
is made visible whenever the demoted definition would have been.
Original commit message (from r283882):
[modules] PR28752: Do not instantiate variable declarations which are not visible.
Original patch by Vassil Vassilev! Changes listed above are mine.
llvm-svn: 284284
This is a patch to implement pr30640.
When a 64bit constant has the same hi/lo words, we can use rldimi to copy the low word into high word of the same register.
This optimization caused failure of test case bperm.ll because of not optimal heuristic in function SelectAndParts64. It chooses AND or ROTATE to extract bit groups from a register, and OR them together. This optimization lowers the cost of loading 64bit constant mask used in AND method, and causes different code sequence. But actually ROTATE method is better in this test case. The reason is in ROTATE method the final OR operation can be avoided since rldimi can insert the rotated bits into target register directly. So this patch also enhances SelectAndParts64 to prefer ROTATE method when the two methods have same cost and there are multiple bit groups need to be ORed together.
Differential Revision: https://reviews.llvm.org/D25521
llvm-svn: 284276
layout for PIE binaries, ask the OS how much stack space is already in use to
avoid stack overflow if we are run with more than 512K of combined command line
arguments + environment variables.
llvm-svn: 284271
Eli noted this potential bug in the post-commit thread for:
https://reviews.llvm.org/rL284239
...but I'm not sure how to trigger it, so there's no test case yet.
llvm-svn: 284268
Summary:
We are using this helper for our 24-bit arithmetic combines, so we are now able to eliminate multi-use operations that mask the high-bits of 24-bit inputs (e.g. and x, 0xffffff)
Reviewers: arsenm, nhaehnle
Subscribers: tony-tye, arsenm, kzhuravl, wdng, nhaehnle, llvm-commits, yaxunl
Differential Revision: https://reviews.llvm.org/D24672
llvm-svn: 284267
Summary:
The main purpose of this new helper is to enable simplifying operations that
have multiple uses. SimplifyDemandedBits does not handle multiple uses
currently, and this new function makes it possible to optimize:
and v1, v0, 0xffffff
mul24 v2, v1, v1 ; Multiply ignoring high 8-bits.
To:
mul24 v2, v0, v0
Where before this would not be optimized, because v1 has multiple uses.
Reviewers: bogner, arsenm
Subscribers: nhaehnle, wdng, llvm-commits
Differential Revision: https://reviews.llvm.org/D24964
llvm-svn: 284266
This commit combines a couple of redundant functions that do availability
attribute context checking into a more correct/simpler one.
Differential revision: https://reviews.llvm.org/D25283
llvm-svn: 284265
Eric Fiselier