[lld] 236197e - [lld-macho] Implement -oso_prefix
Vy Nguyen via llvm-commits
llvm-commits at lists.llvm.org
Fri Oct 22 13:33:04 PDT 2021
Author: Vy Nguyen
Date: 2021-10-22T16:32:42-04:00
New Revision: 236197e2d026193111580bd145f00367ba0c1afb
URL: https://github.com/llvm/llvm-project/commit/236197e2d026193111580bd145f00367ba0c1afb
DIFF: https://github.com/llvm/llvm-project/commit/236197e2d026193111580bd145f00367ba0c1afb.diff
LOG: [lld-macho] Implement -oso_prefix
https://bugs.llvm.org/show_bug.cgi?id=50229
Differential Revision: https://reviews.llvm.org/D112291
Added:
Modified:
lld/MachO/Config.h
lld/MachO/Driver.cpp
lld/MachO/Options.td
lld/MachO/SyntheticSections.cpp
lld/test/MachO/stabs.s
Removed:
################################################################################
diff --git a/lld/MachO/Config.h b/lld/MachO/Config.h
index 0f47015b7607..d23a248aa2ee 100644
--- a/lld/MachO/Config.h
+++ b/lld/MachO/Config.h
@@ -174,6 +174,8 @@ struct Configuration {
bool zeroModTime = false;
+ llvm::StringRef osoPrefix;
+
llvm::MachO::Architecture arch() const { return platformInfo.target.Arch; }
llvm::MachO::PlatformKind platform() const {
diff --git a/lld/MachO/Driver.cpp b/lld/MachO/Driver.cpp
index 527e027381be..542dfacabf02 100644
--- a/lld/MachO/Driver.cpp
+++ b/lld/MachO/Driver.cpp
@@ -1095,6 +1095,29 @@ bool macho::link(ArrayRef<const char *> argsArr, bool canExitEarly,
depTracker =
make<DependencyTracker>(args.getLastArgValue(OPT_dependency_info));
+ config->osoPrefix = args.getLastArgValue(OPT_oso_prefix);
+ if (!config->osoPrefix.empty()) {
+ // Expand special characters, such as ".", "..", or "~", if present.
+ // Note: LD64 only expands "." and not other special characters.
+ // That seems silly to imitate so we will not try to follow it, but rather
+ // just use real_path() to do it.
+
+ // The max path length is 4096, in theory. However that seems quite long
+ // and seems unlikely that any one would want to strip everything from the
+ // path. Hence we've picked a reasonably large number here.
+ SmallString<1024> expanded;
+ if (!fs::real_path(config->osoPrefix, expanded,
+ /*expand_tilde=*/true)) {
+ // Note: LD64 expands "." to be `<current_dir>/`
+ // (ie., it has a slash suffix) whereas real_path() doesn't.
+ // So we have to append '/' to be consistent.
+ StringRef sep = sys::path::get_separator();
+ if (config->osoPrefix.equals(".") && !expanded.endswith(sep))
+ expanded += sep;
+ config->osoPrefix = saver.save(expanded.str());
+ }
+ }
+
// Must be set before any InputSections and Symbols are created.
config->deadStrip = args.hasArg(OPT_dead_strip);
diff --git a/lld/MachO/Options.td b/lld/MachO/Options.td
index a51cd8474c82..0409e7af63a9 100644
--- a/lld/MachO/Options.td
+++ b/lld/MachO/Options.td
@@ -576,7 +576,6 @@ def non_global_symbols_no_strip_list : Separate<["-"], "non_global_symbols_no_st
def oso_prefix : Separate<["-"], "oso_prefix">,
MetaVarName<"<path>">,
HelpText<"Remove the prefix <path> from OSO symbols in the debug map">,
- Flags<[HelpHidden]>,
Group<grp_symtab>;
def add_ast_path : Separate<["-"], "add_ast_path">,
MetaVarName<"<path>">,
diff --git a/lld/MachO/SyntheticSections.cpp b/lld/MachO/SyntheticSections.cpp
index 81f9224a1d2c..8b5c6e95ed1a 100644
--- a/lld/MachO/SyntheticSections.cpp
+++ b/lld/MachO/SyntheticSections.cpp
@@ -860,7 +860,10 @@ void SymtabSection::emitObjectFileStab(ObjFile *file) {
if (!file->archiveName.empty())
path.append({"(", file->getName(), ")"});
- stab.strx = stringTableSection.addString(saver.save(path.str()));
+ StringRef adjustedPath = saver.save(path.str());
+ adjustedPath.consume_front(config->osoPrefix);
+
+ stab.strx = stringTableSection.addString(adjustedPath);
stab.desc = 1;
stab.value = file->modTime;
stabs.emplace_back(std::move(stab));
diff --git a/lld/test/MachO/stabs.s b/lld/test/MachO/stabs.s
index c222536030de..243e6769beb0 100644
--- a/lld/test/MachO/stabs.s
+++ b/lld/test/MachO/stabs.s
@@ -50,6 +50,17 @@
# RUN: FileCheck %s -DDIR=%t -DFOO_PATH=%t/foo.o \
# RUN: -D#TEST_TIME=0x10 -D#FOO_TIME=0x20
+## Check that we emit relative path to object files in OSO entries
+## when -oso_prefix <path> is used.
+# RUN: cd %t && %lld -lSystem test.o foo.o no-debug.o -oso_prefix "%t" -o %t/test-rel
+# RUN: dsymutil -s %t/test-rel | grep 'N_OSO' | FileCheck %s -D#TEST_TIME=0x10 -D#FOO_TIME=0x20 --check-prefix=REL-PATH
+# RUN: cd %t && %lld -lSystem test.o foo.o no-debug.o -oso_prefix "." -o %t/test-rel-dot
+# RUN: dsymutil -s %t/test-rel-dot | grep 'N_OSO' | FileCheck %s -D#TEST_TIME=0x10 -D#FOO_TIME=0x20 --check-prefix=REL-DOT
+## Set HOME to %t (for ~ to expand to)
+# RUN: cd %t && env HOME=%t %lld -lSystem test.o foo.o no-debug.o -oso_prefix "~" -o %t/test-rel-tilde
+# RUN: dsymutil -s %t/test-rel-tilde | grep 'N_OSO' | FileCheck %s -D#TEST_TIME=0x10 -D#FOO_TIME=0x20 --check-prefix=REL-PATH
+
+
# RUN: cd %t && %lld -lSystem test.o foo.a no-debug.o -o %t/test
# RUN: (llvm-objdump --section-headers %t/test; dsymutil -s %t/test) | \
# RUN: FileCheck %s -DDIR=%t -DFOO_PATH=%t/foo.a\(foo.o\) \
@@ -65,6 +76,8 @@
# CHECK: (N_SO ) 00 0000 0000000000000000 '/tmp/test.cpp'
# CHECK-NEXT: (N_OSO ) 03 0001 [[#%.16x,TEST_TIME]] '[[DIR]]/test.o'
+# REL-PATH: (N_OSO ) 03 0001 [[#%.16x,TEST_TIME]] '/test.o'
+# REL-DOT: (N_OSO ) 03 0001 [[#%.16x,TEST_TIME]] 'test.o'
# CHECK-NEXT: (N_STSYM ) [[#%.2d,MORE_DATA_ID + 1]] 0000 [[#%.16x,STATIC:]] '_static_var'
# CHECK-NEXT: (N_FUN ) [[#%.2d,TEXT_ID + 1]] 0000 [[#%.16x,MAIN:]] '_main'
# CHECK-NEXT: (N_FUN ) 00 0000 0000000000000006{{$}}
@@ -87,6 +100,8 @@
# CHECK-NEXT: (N_SO ) 01 0000 0000000000000000{{$}}
# CHECK-NEXT: (N_SO ) 00 0000 0000000000000000 '/foo.cpp'
# CHECK-NEXT: (N_OSO ) 03 0001 [[#%.16x,FOO_TIME]] '[[FOO_PATH]]'
+# REL-PATH-NEXT: (N_OSO ) 03 0001 [[#%.16x,FOO_TIME]] '/foo.o'
+# REL-DOT-NEXT: (N_OSO ) 03 0001 [[#%.16x,FOO_TIME]] 'foo.o'
# CHECK-NEXT: (N_FUN ) [[#%.2d,TEXT_ID + 1]] 0000 [[#%.16x,FOO:]] '_foo'
# CHECK-NEXT: (N_FUN ) 00 0000 0000000000000001{{$}}
# CHECK-NEXT: (N_SO ) 01 0000 0000000000000000{{$}}
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