[lld] r357133 - [ELF] Dump symbols ordered by profiled guided section layout to file.
Rui Ueyama via llvm-commits
llvm-commits at lists.llvm.org
Wed Mar 27 16:52:22 PDT 2019
Author: ruiu
Date: Wed Mar 27 16:52:22 2019
New Revision: 357133
URL: http://llvm.org/viewvc/llvm-project?rev=357133&view=rev
Log:
[ELF] Dump symbols ordered by profiled guided section layout to file.
Patch by Tiancong Wang.
In D36351, Call-Chain Clustering (C3) heuristic is implemented with
option --call-graph-ordering-file <file>.
This patch adds a flag --print-symbol-order=<file> to LLD, and when
specified, it prints out the symbols ordered by the heuristics to the
file. The symbols printout is helpful to those who want to understand
the heuristics and want to reproduce the ordering with
--symbol-ordering-file in later pass.
Differential Revision: https://reviews.llvm.org/D59311
Added:
lld/trunk/test/ELF/cgprofile-print.s
lld/trunk/test/ELF/cgprofile-reproduce.s
Modified:
lld/trunk/ELF/CallGraphSort.cpp
lld/trunk/ELF/Config.h
lld/trunk/ELF/Driver.cpp
lld/trunk/ELF/Options.td
Modified: lld/trunk/ELF/CallGraphSort.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/CallGraphSort.cpp?rev=357133&r1=357132&r2=357133&view=diff
==============================================================================
--- lld/trunk/ELF/CallGraphSort.cpp (original)
+++ lld/trunk/ELF/CallGraphSort.cpp Wed Mar 27 16:52:22 2019
@@ -226,6 +226,27 @@ DenseMap<const InputSectionBase *, int>
for (int SecIndex : C.Sections)
OrderMap[Sections[SecIndex]] = CurOrder++;
+ if (!Config->PrintSymbolOrder.empty()) {
+ std::error_code EC;
+ raw_fd_ostream OS(Config->PrintSymbolOrder, EC, sys::fs::F_None);
+ if (EC) {
+ error("cannot open " + Config->PrintSymbolOrder + ": " + EC.message());
+ return OrderMap;
+ }
+
+ // Print the symbols ordered by C3, in the order of increasing CurOrder
+ // Instead of sorting all the OrderMap, just repeat the loops above.
+ for (const Cluster &C : Clusters)
+ for (int SecIndex : C.Sections)
+ // Search all the symbols in the file of the section
+ // and find out a Defined symbol with name that is within the section.
+ for (Symbol *Sym: Sections[SecIndex]->File->getSymbols())
+ if (!Sym->isSection()) // Filter out section-type symbols here.
+ if (auto *D = dyn_cast<Defined>(Sym))
+ if (Sections[SecIndex] == D->Section)
+ OS << Sym->getName() << "\n";
+ }
+
return OrderMap;
}
Modified: lld/trunk/ELF/Config.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Config.h?rev=357133&r1=357132&r2=357133&view=diff
==============================================================================
--- lld/trunk/ELF/Config.h (original)
+++ lld/trunk/ELF/Config.h Wed Mar 27 16:52:22 2019
@@ -101,6 +101,7 @@ struct Configuration {
llvm::StringRef OptRemarksFilename;
llvm::StringRef OptRemarksPasses;
llvm::StringRef ProgName;
+ llvm::StringRef PrintSymbolOrder;
llvm::StringRef SoName;
llvm::StringRef Sysroot;
llvm::StringRef ThinLTOCacheDir;
Modified: lld/trunk/ELF/Driver.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Driver.cpp?rev=357133&r1=357132&r2=357133&view=diff
==============================================================================
--- lld/trunk/ELF/Driver.cpp (original)
+++ lld/trunk/ELF/Driver.cpp Wed Mar 27 16:52:22 2019
@@ -836,6 +836,8 @@ void LinkerDriver::readConfigs(opt::Inpu
Args.hasFlag(OPT_print_icf_sections, OPT_no_print_icf_sections, false);
Config->PrintGcSections =
Args.hasFlag(OPT_print_gc_sections, OPT_no_print_gc_sections, false);
+ Config->PrintSymbolOrder =
+ Args.getLastArgValue(OPT_print_symbol_order);
Config->Rpath = getRpath(Args);
Config->Relocatable = Args.hasArg(OPT_relocatable);
Config->SaveTemps = Args.hasArg(OPT_save_temps);
Modified: lld/trunk/ELF/Options.td
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Options.td?rev=357133&r1=357132&r2=357133&view=diff
==============================================================================
--- lld/trunk/ELF/Options.td (original)
+++ lld/trunk/ELF/Options.td Wed Mar 27 16:52:22 2019
@@ -274,6 +274,9 @@ defm print_icf_sections: B<"print-icf-se
"List identical folded sections",
"Do not list identical folded sections (default)">;
+defm print_symbol_order: Eq<"print-symbol-order",
+ "Print a symbol order specified by --call-graph-ordering-file into the speficied file">;
+
def pop_state: F<"pop-state">,
HelpText<"Undo the effect of -push-state">;
Added: lld/trunk/test/ELF/cgprofile-print.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/cgprofile-print.s?rev=357133&view=auto
==============================================================================
--- lld/trunk/test/ELF/cgprofile-print.s (added)
+++ lld/trunk/test/ELF/cgprofile-print.s Wed Mar 27 16:52:22 2019
@@ -0,0 +1,37 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: echo "A B 5" > %t.call_graph
+# RUN: echo "B C 50" >> %t.call_graph
+# RUN: echo "C D 40" >> %t.call_graph
+# RUN: echo "D B 10" >> %t.call_graph
+# RUN: ld.lld -e A %t --call-graph-ordering-file %t.call_graph -o %t2 --print-symbol-order=%t3
+# RUN: FileCheck %s --input-file %t3
+
+# CHECK: B
+# CHECK-NEXT: C
+# CHECK-NEXT: D
+# CHECK-NEXT: A
+
+.section .text.A,"ax", at progbits
+.globl A
+A:
+ nop
+
+.section .text.B,"ax", at progbits
+.globl B
+B:
+ nop
+
+.section .text.C,"ax", at progbits
+.globl C
+C:
+ nop
+
+.section .text.D,"ax", at progbits
+.globl D
+D:
+ nop
+
+
+
Added: lld/trunk/test/ELF/cgprofile-reproduce.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/cgprofile-reproduce.s?rev=357133&view=auto
==============================================================================
--- lld/trunk/test/ELF/cgprofile-reproduce.s (added)
+++ lld/trunk/test/ELF/cgprofile-reproduce.s Wed Mar 27 16:52:22 2019
@@ -0,0 +1,42 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: echo "A B 5" > %t.call_graph
+# RUN: echo "B C 50" >> %t.call_graph
+# RUN: echo "C D 40" >> %t.call_graph
+# RUN: echo "D B 10" >> %t.call_graph
+# RUN: ld.lld -e A %t --call-graph-ordering-file %t.call_graph -o %t2 --print-symbol-order=%t3
+# RUN: ld.lld -e A %t --symbol-ordering-file %t3 -o %t2
+# RUN: llvm-readobj -symbols %t2 | FileCheck %s
+
+# CHECK: Name: A
+# CHECK-NEXT: Value: 0x201003
+# CHECK: Name: B
+# CHECK-NEXT: Value: 0x201000
+# CHECK: Name: C
+# CHECK-NEXT: Value: 0x201001
+# CHECK: Name: D
+# CHECK-NEXT: Value: 0x201002
+
+.section .text.A,"ax", at progbits
+.globl A
+A:
+ nop
+
+.section .text.B,"ax", at progbits
+.globl B
+B:
+ nop
+
+.section .text.C,"ax", at progbits
+.globl C
+C:
+ nop
+
+.section .text.D,"ax", at progbits
+.globl D
+D:
+ nop
+
+
+
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