In some cases, the max backedge taken count can be more conservative
than the exact backedge taken count (for instance, because
ScalarEvolution::getRange is not control-flow sensitive whereas
computeExitLimitFromICmp can be). In these cases,
computeExitLimitFromCond (specifically the bit that deals with `and` and
`or` instructions) can create an ExitLimit instance with a
`SCEVCouldNotCompute` max backedge count expression, but a computable
exact backedge count expression. This violates an implicit SCEV
assumption: a computable exact BE count should imply a computable max BE
count.
This change
- Makes the above implicit invariant explicit by adding an assert to
ExitLimit's constructor
- Changes `computeExitLimitFromCond` to be more robust around
conservative max backedge counts
llvm-svn: 258184
According the build bots, clang is using the Registry class somewhere as well. Will reapply with appropriate clang changes at a later point.
llvm-svn: 258159
The Registry class constructs a linked list of nodes whose storage is inside static variables and nodes are added via static initializers. The trick is that those static initializers are in both the LLVM code base, and some random plugin that might get loaded in at runtime. The existing code tries to use C++ templates and their ODR rules to get a single definition of the registry for each type, but, experimentally, this doesn't quite work as designed. (Well, the entire structure doesn't. It might not actually be an ODR problem.)
Previously, when I tried moving the GCStrategy class (along with it's registry) from CodeGen to IR, I ran into a problem where asking the GCStrategyRegistry a question would return inconsistent results depending on whether you asked from CodeGen (where the static initializers still were) or Transforms. My best guess is that this is a result of either a) an order of initialization error, or b) we ended up with two copies of the registry being created. I remember at the time having convinced myself it was probably (b), but I don't have any of my notes around from that investigation any more.
See http://reviews.llvm.org/rL226311 for the original patch in question.
This patch tries to remove the possibility of (b) above. (a) was already fixed in change 258109.
Differential Revision: http://reviews.llvm.org/D16170
llvm-svn: 258157
This patch creates the profile data variable before lowering the profile intrinsics.
Reviewers: davidxl, silvas
Differential Revision: http://reviews.llvm.org/D16015
llvm-svn: 258156
Our loop construct is not a way to identify cycles in the CFG. This wasn't immediately obvious from the header, so clarify that fact.
The motivation for this was that I just fixed a out of tree bug due to a mistaken assumption (on my part) on what a Loop actually was. While it was fresh in my mind, I wanted to document the key point.
llvm-svn: 258154
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555
As with D15937, the intent of the patch is to preserve the current behavior of the transform
except that we use the pow call's 'fast' attribute as a trigger rather than a function-level
attribute.
The TODO comment notes a potential follow-on patch that would propagate FMF to the new
instructions.
Differential Revision: http://reviews.llvm.org/D16122
llvm-svn: 258153
Summary:
add_version_info_from_vcs was setting SVN_REVISION to the last fetched
svn revision when using git svn instead of the svn revision
corresponding to HEAD. This leads to conflicts with the definition of
SVN_REVISION in SVNVersion.inc generated by GetSVN.cmake when HEAD is
not the most recently fetched svn revision.
Use 'git svn info' to determine SVN_REVISION when git svn is being used
instead (as is done in GetSVN.cmake).
Reviewers: beanz
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16299
llvm-svn: 258148
Summary:
GEPOperator: provide getResultElementType alongside getSourceElementType.
This is made possible by adding a result element type field to GetElementPtrConstantExpr, which GetElementPtrInst already has.
GEP: replace get(Pointer)ElementType uses with get{Source,Result}ElementType.
Reviewers: mjacob, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16275
llvm-svn: 258145
Teach the register stackifier to rematerialize constants that have multiple
uses instead of leaving them in registers. In the WebAssembly encoding, it's
the same code size to materialize most constants as it is to read a value
from a register.
llvm-svn: 258142
The value size was always 1 or 0, so we don't need to store it.
In a no asserts build this takes the testcase of pr26208 from 11 to 10
seconds.
llvm-svn: 258141
According to x86 spec "xlat m8" is a legal instruction and it is equivalent to "xlatb".
Differential Revision: http://reviews.llvm.org/D15150
llvm-svn: 258135
The following are legal according to X86 spec:
ins mem, DX
outs DX, mem
lods mem
stos mem
scas mem
cmps mem, mem
movs mem, mem
Differential Revision: http://reviews.llvm.org/D14827
llvm-svn: 258132
This commit changes the default on our lowering of vectors-of-pointers from splitting in RS4GC to reporting them in the final stack map. All of the changes to do so are already in place and tested. Assuming no problems are unearthed in the next week, we will be deleting the old code entirely next Monday.
llvm-svn: 258111
Combine a bunch of small files into a single, still rather small, file. The primary purpose of this is to get all of the static initializers into a single file so as to have a well defined order of initialization.
llvm-svn: 258109
Summary:
This is a companion patch for http://reviews.llvm.org/D16124.
Internalized symbols increase the size of strongly-connected components in
SCC-based module splitting and thus reduce the amount of parallelism. This
patch records the original linkage of non-local symbols prior to
internalization and then restores it just before splitting/CodeGen. This is
also useful for cases where the linker requires symbols to remain external, for
instance, so they can be placed according to linker script rules.
It's currently under its own flag (-restore-globals) but should eventually
share a common flag with D16124.
Reviewers: joker.eph, pcc
Subscribers: slarin, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D16229
llvm-svn: 258100
This breaks the tests that were meant for testing
64-bit inline immediates, so move those to shl where
they won't be broken up.
This should be repeated for the other related bit ops.
llvm-svn: 258095
Sanjoy Das