Commit Graph

12 Commits

Author SHA1 Message Date
Clement Courbet 9431b72ce9 [llvm-exegesis] Add loop mode for repeating the snippet.
Summary:
Before this change the Executable function was made by duplicating the
snippet. This change adds a --repetion-mode={loop|duplicate} flag that
allows choosing between this behaviour and wrapping the snippet instructions
in a loop.

The new mode can help measurements when the snippet fits in the DSB by
short-cirtcuiting decoding. The loop adds a dec + jmp to the measurements, but
since these are not part of the critical path, they execute in parallel
with the measured code and do not impact measurements in practice.

Overview of the change:
 - New SnippetRepetitor abstraction that handles repeating the snippet.
   The assembler delegates repeating the instructions to this class.
 - ExegesisTarget learns how to decrement loop counter and jump.
 - Some refactoring of the assembler into FunctionFiller/BasicBlockFiller.

Reviewers: gchatelet

Subscribers: mgorny, tschuett, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68125

llvm-svn: 373083
2019-09-27 12:56:24 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Fangrui Song 32401afd8c [llvm-exegesis] Move namespace exegesis inside llvm::
Summary:
This allows simplifying references of llvm::foo with foo when the needs
come in the future.

Reviewers: courbet, gchatelet

Reviewed By: gchatelet

Subscribers: javed.absar, tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D53455

llvm-svn: 344922
2018-10-22 17:10:47 +00:00
Guillaume Chatelet c96a97bac7 [llvm-exegesis] Improve Register Setup (roll forward of D51856).
Summary:
Added function to set a register to a particular value + tests.
Add EFLAGS test, use new setRegTo instead of setRegToConstant.

Reviewers: courbet, javed.absar

Subscribers: llvm-commits, tschuett, mgorny

Differential Revision: https://reviews.llvm.org/D52297

llvm-svn: 342644
2018-09-20 12:22:18 +00:00
Simon Pilgrim 0242689725 Revert rL342466: [llvm-exegesis] Improve Register Setup.
rL342465 is breaking the MSVC buildbots, but I need to revert this dependent revision as well.

Summary:
Added function to set a register to a particular value + tests.
Add EFLAGS test, use new setRegTo instead of setRegToConstant.

Reviewers: courbet, javed.absar

Subscribers: mgorny, tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D51856

llvm-svn: 342489
2018-09-18 15:35:49 +00:00
Guillaume Chatelet 937f3fedec [llvm-exegesis] Improve Register Setup.
Summary:
Added function to set a register to a particular value + tests.
Add EFLAGS test, use new setRegTo instead of setRegToConstant.

Reviewers: courbet, javed.absar

Subscribers: mgorny, tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D51856

llvm-svn: 342466
2018-09-18 11:26:48 +00:00
Argyrios Kyrtzidis c30340b207 Add header guards to some headers that are missing them
Also adjust some of dsymutil's headers to put the header guards at the top,
otherwise the compiler will not recognize them as header guards.

llvm-svn: 341323
2018-09-03 16:22:05 +00:00
Guillaume Chatelet fb94354d2d [llvm-exegesis] Provide a way to handle memory instructions.
Summary:
And implement memory instructions on X86.

This fixes PR36906.

Reviewers: gchatelet

Reviewed By: gchatelet

Subscribers: lebedev.ri, filcab, mgorny, tschuett, RKSimon, llvm-commits

Differential Revision: https://reviews.llvm.org/D48935

llvm-svn: 338567
2018-08-01 14:41:45 +00:00
Clement Courbet 4860b98443 [llvm-exegesis] Get the BenchmarkRunner from the ExegesisTarget.
Summary:
This allows targets to override code generation for some instructions.
As an example of override, this also moves ad-hoc instruction filtering
for X86 into the X86 ExegesisTarget.

Reviewers: gchatelet

Subscribers: mgorny, tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D48587

llvm-svn: 335582
2018-06-26 08:49:30 +00:00
Clement Courbet a51efc266c [llvm-exegesis] Generate snippet setup code.
Summary:
This ensures that the snippet always sees the same values for registers,
making measurements reproducible.
This will also allow exploring different values.

Reviewers: gchatelet

Subscribers: tschuett, llvm-commits

Differential Revision: https://reviews.llvm.org/D48542

llvm-svn: 335465
2018-06-25 13:12:02 +00:00
Clement Courbet 3bbdea4a44 [llvm-exegesis][NFC] Remove dead function.
llvm-svn: 332597
2018-05-17 11:51:49 +00:00
Clement Courbet 0e69e2d747 reland r332579: [llvm-exegesis] Update to cover latency through another opcode.
Restructuring the code to measure latency and uops.
The end goal is to have this program spawn another process to deal with SIGILL and other malformed programs. It is not yet the case in this redesign, it is still the main program that runs the code (and may crash).
It now uses BitVector instead of Graph for performance reasons.

https://reviews.llvm.org/D46821

(with fixed ARM tests)

Authored by Guillaume Chatelet

llvm-svn: 332592
2018-05-17 10:52:18 +00:00