https://github.com/tstellar updated
https://github.com/llvm/llvm-project/pull/77347
>From 127e2ae83f33843cfb9c5cca314afa2fc9844239 Mon Sep 17 00:00:00 2001
From: Tom Stellard
Date: Sat, 6 Jan 2024 07:46:01 +
Subject: [PATCH 1/4] [CMake][PGO] Use check-clang target to generate profdata
for PGO builds
When doing a multi-stage PGO build of clang, run the check-clang and
check-llvm targets using the instrumented clang and use that profile
data for building the final stage2 clang. This is what is recommended
by our official documentation:
https://llvm.org/docs/HowToBuildWithPGO.html#building-clang-with-pgo
I benchmarked this change by compiling the SemaChecking.cpp file from
clang. Using check-clang/check-llvm to generate the profile data gives a 25%
speedup
in the PGO+LTO stage2 clang when compared to the stage1 clang (no-LTO).
Prior to this change, I was only seeing ~5% speedup when comparing the
stage2 and stage1 builds.
---
clang/utils/perf-training/CMakeLists.txt | 6 +++---
clang/utils/perf-training/perf-helper.py | 16 +---
2 files changed, 12 insertions(+), 10 deletions(-)
diff --git a/clang/utils/perf-training/CMakeLists.txt
b/clang/utils/perf-training/CMakeLists.txt
index c6d51863fb1b5c..95ff8115aa538b 100644
--- a/clang/utils/perf-training/CMakeLists.txt
+++ b/clang/utils/perf-training/CMakeLists.txt
@@ -15,7 +15,7 @@ if(LLVM_BUILD_INSTRUMENTED)
)
add_custom_target(clear-profraw
-COMMAND "${Python3_EXECUTABLE}" ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py
clean ${CMAKE_CURRENT_BINARY_DIR} profraw
+COMMAND "${Python3_EXECUTABLE}" ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py
clean ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR}/profiles/ profraw
COMMENT "Clearing old profraw data")
if(NOT LLVM_PROFDATA)
@@ -26,9 +26,9 @@ if(LLVM_BUILD_INSTRUMENTED)
message(STATUS "To enable merging PGO data LLVM_PROFDATA has to point to
llvm-profdata")
else()
add_custom_target(generate-profdata
- COMMAND "${Python3_EXECUTABLE}"
${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py merge ${LLVM_PROFDATA}
${CMAKE_CURRENT_BINARY_DIR}/clang.profdata ${CMAKE_CURRENT_BINARY_DIR}
+ COMMAND "${Python3_EXECUTABLE}"
${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py merge ${LLVM_PROFDATA}
${CMAKE_CURRENT_BINARY_DIR}/clang.profdata ${CMAKE_CURRENT_BINARY_DIR}
${CMAKE_BINARY_DIR}/profiles/
COMMENT "Merging profdata"
- DEPENDS generate-profraw)
+ DEPENDS generate-profraw check-clang check-llvm)
endif()
endif()
diff --git a/clang/utils/perf-training/perf-helper.py
b/clang/utils/perf-training/perf-helper.py
index 99d6ab6ef0..bd8f74c9c2e129 100644
--- a/clang/utils/perf-training/perf-helper.py
+++ b/clang/utils/perf-training/perf-helper.py
@@ -30,26 +30,28 @@ def findFilesWithExtension(path, extension):
def clean(args):
-if len(args) != 2:
+if len(args) < 2:
print(
-"Usage: %s clean \n" % __file__
+"Usage: %s clean \n" % __file__
+ "\tRemoves all files with extension from ."
)
return 1
-for filename in findFilesWithExtension(args[0], args[1]):
-os.remove(filename)
+for path in args[1:-1]:
+ for filename in findFilesWithExtension(path, args[-1]):
+ os.remove(filename)
return 0
def merge(args):
-if len(args) != 3:
+if len(args) < 3:
print(
-"Usage: %s merge \n" % __file__
+"Usage: %s merge \n" % __file__
+ "\tMerges all profraw files from path into output."
)
return 1
cmd = [args[0], "merge", "-o", args[1]]
-cmd.extend(findFilesWithExtension(args[2], "profraw"))
+for i in range(2, len(args)):
+ cmd.extend(findFilesWithExtension(args[i], "profraw"))
subprocess.check_call(cmd)
return 0
>From 4f7734584af3aa9a18bde17349ceccbef3658c53 Mon Sep 17 00:00:00 2001
From: Tom Stellard
Date: Mon, 8 Jan 2024 18:07:31 +
Subject: [PATCH 2/4] Fix python formatting
---
clang/utils/perf-training/perf-helper.py | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/clang/utils/perf-training/perf-helper.py
b/clang/utils/perf-training/perf-helper.py
index bd8f74c9c2e129..844aa274f049aa 100644
--- a/clang/utils/perf-training/perf-helper.py
+++ b/clang/utils/perf-training/perf-helper.py
@@ -37,8 +37,8 @@ def clean(args):
)
return 1
for path in args[1:-1]:
- for filename in findFilesWithExtension(path, args[-1]):
- os.remove(filename)
+for filename in findFilesWithExtension(path, args[-1]):
+os.remove(filename)
return 0
@@ -51,7 +51,7 @@ def merge(args):
return 1
cmd = [args[0], "merge", "-o", args[1]]
for i in range(2, len(args)):
- cmd.extend(findFilesWithExtension(args[i], "profraw"))
+cmd.extend(findFilesWithExtension(args[i], "profraw"))
subprocess.check_call(cmd)
return 0
>From
