Commit Graph

8 Commits

Author SHA1 Message Date
Fangrui Song 5a8fd65700 [llvm-mca] Move namespace mca inside llvm::
Summary: This allows to remove `using namespace llvm;` in those *.cpp files

When we want to revisit the decision (everything resides in llvm::mca::*) in the future, we can move things to a nested namespace of llvm::mca::, to conceptually make them separate from the rest of llvm::mca::*

Reviewers: andreadb, mattd

Reviewed By: andreadb

Subscribers: javed.absar, tschuett, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D53407

llvm-svn: 345612
2018-10-30 15:56:08 +00:00
Andrea Di Biagio 84d0051310 [llvm-mca] Removed dependency on mca::SourcMgr in some Views. NFC
llvm-svn: 345376
2018-10-26 10:48:04 +00:00
Andrea Di Biagio 7be45b0f85 [llvm-mca] Refactor class SourceMgr. NFCI
Added begin()/end() methods to allow the usage of SourceMgr in foreach loops.
With this change, method getMCInstFromIndex() (as well as a couple of other
methods) are now redundant, and can be removed from the public interface.

llvm-svn: 345147
2018-10-24 15:06:27 +00:00
Andrea Di Biagio 7f2230ff16 [llvm-mca] correctly initialize field 'CycleRetired' in the TimelineView.
This fixes a [-Wmissing-field-initializers] warning reported by buildbot
lld-x86_64-darwin13, build #25152.

llvm-svn: 341056
2018-08-30 11:17:58 +00:00
Andrea Di Biagio 8b647dcf4b [llvm-mca] Report the number of dispatched micro opcodes in the DispatchStatistics view.
This patch introduces the following changes to the DispatchStatistics view:
 * DispatchStatistics now reports the number of dispatched opcodes instead of
   the number of dispatched instructions.
 * The "Dynamic Dispatch Stall Cycles" table now also reports the percentage of
   stall cycles against the total simulated cycles.

This change allows users to easily compare dispatch group sizes with the
processor DispatchWidth.
Before this change, it was difficult to correlate the two numbers, since
DispatchStatistics view reported numbers of instructions (instead of opcodes).
DispatchWidth defines the maximum size of a dispatch group in terms of number of
micro opcodes.

The other change introduced by this patch is related to how DispatchStage
generates "instruction dispatch" events.
In particular:
 * There can be multiple dispatch events associated with a same instruction
 * Each dispatch event now encapsulates the number of dispatched micro opcodes.

The number of micro opcodes declared by an instruction may exceed the processor
DispatchWidth. Therefore, we cannot assume that instructions are always fully
dispatched in a single cycle.
DispatchStage knows already how to handle instructions declaring a number of
opcodes bigger that DispatchWidth. However, DispatchStage always emitted a
single instruction dispatch event (during the first simulated dispatch cycle)
for instructions dispatched.

With this patch, DispatchStage now correctly notifies multiple dispatch events
for instructions that cannot be dispatched in a single cycle.

A few views had to be modified. Views can no longer assume that there can only
be one dispatch event per instruction.

Tests (and docs) have been updated.

Differential Revision: https://reviews.llvm.org/D51430

llvm-svn: 341055
2018-08-30 10:50:20 +00:00
Andrea Di Biagio 4269d64b20 [llvm-mca] Initialize each element in vector TimelineView::UsedBuffers to a default invalid buffer descriptor. NFCI
Also change the default buffer size for UsedBuffer entries to -1 (i.e. "unknown
size"). No functional change intended.

llvm-svn: 340830
2018-08-28 15:07:11 +00:00
Andrea Di Biagio d17d371c40 [llvm-mca][TimelineView] Force the same number of executions for every entry in the 'wait-times' table.
This patch also uses colors to highlight problematic wait-time entries.
A problematic entry is an entry with an high wait time that tends to match (or
exceed) the size of the scheduler's buffer.

Color RED is used if an instruction had to wait an average number of cycles
which is bigger than (or equal to) the size of the underlying scheduler's
buffer.
Color YELLOW is used if the time (in cycles) spend waiting for the
operands or pipeline resources is bigger than half the size of the underlying
scheduler's buffer.
Color MAGENTA is used if an instruction does not consume buffer resources
according to the scheduling model.

llvm-svn: 340825
2018-08-28 14:27:01 +00:00
Matt Davis 10aa09f008 [llvm-mca] Move views and stats into a Views subdir. NFC.
llvm-svn: 340645
2018-08-24 20:24:53 +00:00