From 7f50100cfa2b1bc3ac33a6eebaccd4c3af9bd1dc Mon Sep 17 00:00:00 2001
From: Kevin Enderby <enderby@apple.com>
Date: Fri, 11 Jul 2014 20:30:00 +0000
Subject: [PATCH] =?UTF-8?q?Add=20the=20"-s"=20flag=20to=20llvm-nm=20for=20?=
=?UTF-8?q?Mach-O=20files=20that=20prints=20symbols=20only=20in=20the=20sp?=
=?UTF-8?q?ecified=20section.=20=20This=20is=20same=20functionality=20as?=
=?UTF-8?q?=20darwin=E2=80=99s=20nm(1)=20"-s"=20flag.?=
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There is one FIXME in the code and I’m all ears to anyone that can help me
with that. This option takes exactly two strings and should be allowed
anywhere on the command line. Such that "llvm-nm -s __TEXT __text foo.o"
would work. But that does not as the CommandLine Library does not have a
way to make this work as far as I can tell. For now the "-s __TEXT __text"
has to be last on the command line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212842 91177308-0d34-0410-b5e6-96231b3b80d8
---
test/Object/nm-trivial-object.test | 8 ++++
tools/llvm-nm/llvm-nm.cpp | 70 ++++++++++++++++++++++++++++++
2 files changed, 78 insertions(+)
diff --git a/test/Object/nm-trivial-object.test b/test/Object/nm-trivial-object.test
index 656d6b00cd3..93ddb0c56c1 100644
--- a/test/Object/nm-trivial-object.test
+++ b/test/Object/nm-trivial-object.test
@@ -22,6 +22,8 @@ RUN: llvm-nm -j %p/Inputs/macho-text-data-bss.macho-x86_64 \
RUN: | FileCheck %s -check-prefix macho-j
RUN: llvm-nm -r %p/Inputs/macho-text-data-bss.macho-x86_64 \
RUN: | FileCheck %s -check-prefix macho-r
+RUN: llvm-nm %p/Inputs/macho-text-data-bss.macho-x86_64 -s __DATA __data \
+RUN: | FileCheck %s -check-prefix macho-s
RUN: llvm-nm %p/Inputs/common.coff-i386 \
RUN: | FileCheck %s -check-prefix COFF-COMMON
RUN: llvm-nm %p/Inputs/relocatable-with-section-address.elf-x86-64 \
@@ -99,6 +101,12 @@ macho-r-NEXT: 000000000000000c D _d
macho-r-NEXT: 0000000000000070 b _b
macho-r-NEXT: 0000000000000030 s EH_frame0
+macho-s: 000000000000000c D _d
+macho-s-NOT: 0000000000000048 S _t.eh
+macho-s-NOT: 0000000000000000 T _t
+macho-s-NOT: 0000000000000070 b _b
+macho-s-NOT: 0000000000000030 s EH_frame0
+
Test that nm uses addresses even with ELF .o files.
ELF-SEC-ADDR64: 0000000000000058 D a
ELF-SEC-ADDR64-NEXT: 000000000000005c D b
diff --git a/tools/llvm-nm/llvm-nm.cpp b/tools/llvm-nm/llvm-nm.cpp
index 3bd9ef905a2..e09d682d81d 100644
--- a/tools/llvm-nm/llvm-nm.cpp
+++ b/tools/llvm-nm/llvm-nm.cpp
@@ -136,6 +136,16 @@ cl::opt<bool> JustSymbolName("just-symbol-name",
cl::desc("Print just the symbol's name"));
cl::alias JustSymbolNames("j", cl::desc("Alias for --just-symbol-name"),
cl::aliasopt(JustSymbolName));
+
+// FIXME: This option takes exactly two strings and should be allowed anywhere
+// on the command line. Such that "llvm-nm -s __TEXT __text foo.o" would work.
+// But that does not as the CommandLine Library does not have a way to make
+// this work. For now the "-s __TEXT __text" has to be last on the command
+// line.
+cl::list<std::string> SegSect("s", cl::Positional, cl::ZeroOrMore,
+ cl::desc("Dump only symbols from this segment "
+ "and section name, Mach-O only"));
+
bool PrintAddress = true;
bool MultipleFiles = false;
@@ -714,6 +724,46 @@ static char getNMTypeChar(SymbolicFile *Obj, basic_symbol_iterator I) {
return Ret;
}
+// getNsectForSegSect() is used to implement the Mach-O "-s segname sectname"
+// option to dump only those symbols from that section in a Mach-O file.
+// It is called once for each Mach-O file from dumpSymbolNamesFromObject()
+// to get the section number for that named section from the command line
+// arguments. It returns the section number for that section in the Mach-O
+// file or zero it is not present.
+static unsigned getNsectForSegSect(MachOObjectFile *Obj) {
+ unsigned Nsect = 1;
+ for (section_iterator I = Obj->section_begin(), E = Obj->section_end();
+ I != E; ++I) {
+ DataRefImpl Ref = I->getRawDataRefImpl();
+ StringRef SectionName;
+ Obj->getSectionName(Ref, SectionName);
+ StringRef SegmentName = Obj->getSectionFinalSegmentName(Ref);
+ if (SegmentName == SegSect[0] && SectionName == SegSect[1])
+ return Nsect;
+ Nsect++;
+ }
+ return 0;
+}
+
+// getNsectInMachO() is used to implement the Mach-O "-s segname sectname"
+// option to dump only those symbols from that section in a Mach-O file.
+// It is called once for each symbol in a Mach-O file from
+// dumpSymbolNamesFromObject() and returns the section number for that symbol
+// if it is in a section, else it returns 0.
+static unsigned getNsectInMachO(MachOObjectFile &Obj, basic_symbol_iterator I) {
+ DataRefImpl Symb = I->getRawDataRefImpl();
+ if (Obj.is64Bit()) {
+ MachO::nlist_64 STE = Obj.getSymbol64TableEntry(Symb);
+ if ((STE.n_type & MachO::N_TYPE) == MachO::N_SECT)
+ return STE.n_sect;
+ return 0;
+ }
+ MachO::nlist STE = Obj.getSymbolTableEntry(Symb);
+ if ((STE.n_type & MachO::N_TYPE) == MachO::N_SECT)
+ return STE.n_sect;
+ return 0;
+}
+
static void dumpSymbolNamesFromObject(SymbolicFile *Obj, bool printName) {
basic_symbol_iterator IBegin = Obj->symbol_begin();
basic_symbol_iterator IEnd = Obj->symbol_end();
@@ -729,6 +779,16 @@ static void dumpSymbolNamesFromObject(SymbolicFile *Obj, bool printName) {
}
std::string NameBuffer;
raw_string_ostream OS(NameBuffer);
+ // If a "-s segname sectname" option was specified and this is a Mach-O
+ // file get the section number for that section in this object file.
+ unsigned int Nsect = 0;
+ MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(Obj);
+ if (SegSect.size() != 0 && MachO) {
+ Nsect = getNsectForSegSect(MachO);
+ // If this section is not in the object file no symbols are printed.
+ if (Nsect == 0)
+ return;
+ }
for (basic_symbol_iterator I = IBegin; I != IEnd; ++I) {
uint32_t SymFlags = I->getFlags();
if (!DebugSyms && (SymFlags & SymbolRef::SF_FormatSpecific))
@@ -740,6 +800,11 @@ static void dumpSymbolNamesFromObject(SymbolicFile *Obj, bool printName) {
continue;
}
}
+ // If a "-s segname sectname" option was specified and this is a Mach-O
+ // file and this section appears in this file, Nsect will be non-zero then
+ // see if this symbol is a symbol from that section and if not skip it.
+ if (Nsect && Nsect != getNsectInMachO(*MachO, I))
+ continue;
NMSymbol S;
S.Size = UnknownAddressOrSize;
S.Address = UnknownAddressOrSize;
@@ -1047,6 +1112,11 @@ int main(int argc, char **argv) {
}
}
+ if (SegSect.size() != 0 && SegSect.size() != 2)
+ error("bad number of arguments (must be two arguments)",
+ "for the -s option");
+
+
std::for_each(InputFilenames.begin(), InputFilenames.end(),
dumpSymbolNamesFromFile);