This commit does not complete the type units feature - there are issues
around fission support (skeletal type units, pubtypes/pubnames) and
hashing of some types including those containing references to types in
other type units.
llvm-svn: 197073
DAGCombiner could fold (truncate (load)) -> smaller load if the original
load was the width of the truncation result or wider. This patch extends
it to handle cases where the original load was narrower (and so the
extension type stays the same).
llvm-svn: 197030
This hook reverses the order of assignment for local live ranges. This
will generally allocate shorter local live ranges first. For targets with
many registers, this could reduce regalloc compile time by a large
factor. It should still achieve optimal coloring; however, it can change
register eviction decisions. It is disabled by default for two reasons:
(1) Top-down allocation is simpler and easier to debug for targets that
don't benefit from reversing the order.
(2) Bottom-up allocation could result in poor evicition decisions on some
targets affecting the performance of compiled code.
llvm-svn: 197001
This re-lands commit r196876, which was reverted in r196879.
The tests have been fixed to pass on platforms with a stack alignment
larger than 4.
Update to clang side tests will land shortly.
llvm-svn: 196939
One unusual feature of the z architecture is that the result of a
previous load can be reused indefinitely for subsequent loads, even if
a cache-coherent store to that location is performed by another CPU.
A special serializing instruction must be used if you want to force
a load to be reattempted.
Since volatile loads are not supposed to be omitted in this way,
we should insert a serializing instruction before each such load.
The same goes for atomic loads.
The patch implements this at the IR->DAG boundary, in a similar way
to atomic fences. It is a no-op for targets other than SystemZ.
llvm-svn: 196905
For stack frames requiring realignment, three pointers may be needed:
- ebp to address incoming arguments
- esi (could be any callee-saved register) to address locals
- esp to address outgoing arguments
We would use esi unconditionally without verifying that it did not
conflict with inline assembly.
This change doesn't do the verification, it simply emits a fatal error
on functions that use stack realignment, dynamic SP adjustments, and
inline assembly.
Because stack realignment is common on Windows, we also no longer assume
that MS inline assembly clobbers esp. Instead, we analyze the inline
instructions for implicit definitions and check if esp is there. If so,
we require the use of a base pointer and consider it in the condition
above.
Mostly fixes PR16830, but we could try harder to find a non-conflicting
base pointer.
Reviewers: sunfish
Differential Revision: http://llvm-reviews.chandlerc.com/D1317
llvm-svn: 196876
These helper classes take care of the book-keeping the drives the
GenericScheduler heuristics. It is likely that developers writing
target-specific schedulers that work similarly to GenericScheduler
will want to use these helpers too. The immediate goal is to develop a
GenericPostScheduler that can run in place of the old PostRAScheduler,
but will use the new machine model.
No functionality change intended.
llvm-svn: 196643
This removes another case of spooky action at a distance (building the
same label names in multiple places creating an implicit dependency
between those places) and helps pave the way for type units.
llvm-svn: 196617
This more accurately represents the actual walk - pubnames/pubtypes are
emitted into the .o, not the .dwo, and reference the skeletons not the
full units.
Use the newly established ID->index invariant to lookup the underlying
full unit to retrieve its public names and types.
llvm-svn: 196601
This simplifies reasoning about the code and enables simple navigation
from a skeleton to its full unit. (currently there are no type unit
skeletons, so the skeleton list doesn't have the same ID == index
property)
Eventually we should get rid of this ID and just store the labels we
need as the IDs are allowing this code to create difficult to
manage/understand associations (loops over non-skeletal units are
implicitly referencing their skeletal units during pub* emission, for
example). It may be necessary to have some kind of skeleton->full unit
association and a more direct pointer or similar device would be
preferable than an index.
llvm-svn: 196600
Not only does it trigger -Wparentheses, I think the assert actually
relies on incorrect operator precedence.
Also, the grammar as questionable, but I might not know enough about the
problem at hand.
llvm-svn: 196567
This allows a target to use MI-Sched as an in-order scheduler that
will model strict resource conflicts without defining a processor
itinerary. Instead, the target can now use the new per-operand machine
model and define in-order resources with BufferSize=0. For example,
this would allow restricting the type of operations that can be formed
into a dispatch group. (Normally NumMicroOps is sufficient to enforce
dispatch groups).
If the intent is to model latency in in-order pipeline, as opposed to
resource conflicts, then a resource with BufferSize=1 should be
defined instead.
This feature is only casually tested as there are no in-tree targets
using it yet. However, Hal will be experimenting with POWER7.
llvm-svn: 196517
This just extends the existing hack. It should be enough to get a reproducible bootstrap
on 32 bits.
I will open a bug to track getting a real fix for this.
llvm-svn: 196462
