[ELF][AArch64] Rename --force-bti to -z force-bti and --pac-plt to -z pac-plt

Summary:
The original design used --foo but the upstream complained that ELF only
options should be -z foo. See https://sourceware.org/ml/binutils/2019-04/msg00151.html
https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=8bf6d176b0a442a8091d338d4af971591d19922c
made the rename.

Our --force-bti and --pac-plt implement the same functionality, so it
seems wise to be consistent with GNU ld.

Reviewed By: peter.smith

Subscribers: emaste, arichardson, kristof.beyls, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71327

7 files changed, 34 insertions, 37 deletions

diff --git a/lld/ELF/Driver.cpp b/lld/ELF/Driver.cpp
index a0987259d24..c721e872e12 100644
--- a/lld/ELF/Driver.cpp
+++ b/lld/ELF/Driver.cpp
@@ -354,9 +354,9 @@ static void checkOptions() {
 
   if (config->emachine != EM_AARCH64) {
     if (config->pacPlt)
-      error("--pac-plt only supported on AArch64");
+      error("-z pac-plt only supported on AArch64");
     if (config->forceBTI)
-      error("--force-bti only supported on AArch64");
+      error("-z force-bti only supported on AArch64");
   }
 }
 
@@ -412,17 +412,18 @@ static GnuStackKind getZGnuStack(opt::InputArgList &args) {
 
 static bool isKnownZFlag(StringRef s) {
   return s == "combreloc" || s == "copyreloc" || s == "defs" ||
-         s == "execstack" || s == "global" || s == "hazardplt" ||
-         s == "ifunc-noplt" || s == "initfirst" || s == "interpose" ||
-         s == "keep-text-section-prefix" || s == "lazy" || s == "muldefs" ||
-         s == "separate-code" || s == "separate-loadable-segments" ||
-         s == "nocombreloc" || s == "nocopyreloc" || s == "nodefaultlib" ||
-         s == "nodelete" || s == "nodlopen" || s == "noexecstack" ||
-         s == "nognustack" ||
+         s == "execstack" || s == "force-bti" || s == "global" ||
+         s == "hazardplt" || s == "ifunc-noplt" || s == "initfirst" ||
+         s == "interpose" || s == "keep-text-section-prefix" || s == "lazy" ||
+         s == "muldefs" || s == "separate-code" ||
+         s == "separate-loadable-segments" || s == "nocombreloc" ||
+         s == "nocopyreloc" || s == "nodefaultlib" || s == "nodelete" ||
+         s == "nodlopen" || s == "noexecstack" || s == "nognustack" ||
          s == "nokeep-text-section-prefix" || s == "norelro" ||
          s == "noseparate-code" || s == "notext" || s == "now" ||
-         s == "origin" || s == "relro" || s == "retpolineplt" ||
-         s == "rodynamic" || s == "text" || s == "undefs" || s == "wxneeded" ||
+         s == "origin" || s == "pac-plt" || s == "relro" ||
+         s == "retpolineplt" || s == "rodynamic" || s == "text" ||
+         s == "undefs" || s == "wxneeded" ||
          s.startswith("common-page-size=") || s.startswith("max-page-size=") ||
          s.startswith("stack-size=");
 }
@@ -878,7 +879,7 @@ static void readConfigs(opt::InputArgList &args) {
   config->fini = args.getLastArgValue(OPT_fini, "_fini");
   config->fixCortexA53Errata843419 = args.hasArg(OPT_fix_cortex_a53_843419);
   config->fixCortexA8 = args.hasArg(OPT_fix_cortex_a8);
-  config->forceBTI = args.hasArg(OPT_force_bti);
+  config->forceBTI = hasZOption(args, "force-bti");
   config->requireCET = args.hasArg(OPT_require_cet);
   config->gcSections = args.hasFlag(OPT_gc_sections, OPT_no_gc_sections, false);
   config->gnuUnique = args.hasFlag(OPT_gnu_unique, OPT_no_gnu_unique, true);
@@ -917,7 +918,7 @@ static void readConfigs(opt::InputArgList &args) {
   config->optimize = args::getInteger(args, OPT_O, 1);
   config->orphanHandling = getOrphanHandling(args);
   config->outputFile = args.getLastArgValue(OPT_o);
-  config->pacPlt = args.hasArg(OPT_pac_plt);
+  config->pacPlt = hasZOption(args, "pac-plt");
   config->pie = args.hasFlag(OPT_pie, OPT_no_pie, false);
   config->printIcfSections =
       args.hasFlag(OPT_print_icf_sections, OPT_no_print_icf_sections, false);
@@ -1704,7 +1705,7 @@ template <class ELFT> static uint32_t getAndFeatures() {
   for (InputFile *f : objectFiles) {
     uint32_t features = cast<ObjFile<ELFT>>(f)->andFeatures;
     if (config->forceBTI && !(features & GNU_PROPERTY_AARCH64_FEATURE_1_BTI)) {
-      warn(toString(f) + ": --force-bti: file does not have BTI property");
+      warn(toString(f) + ": -z force-bti: file does not have BTI property");
       features |= GNU_PROPERTY_AARCH64_FEATURE_1_BTI;
     } else if (!features && config->requireCET)
       error(toString(f) + ": --require-cet: file is not compatible with CET");
diff --git a/lld/ELF/Options.td b/lld/ELF/Options.td
index 101fc438f70..b86a670915c 100644
--- a/lld/ELF/Options.td
+++ b/lld/ELF/Options.td
@@ -180,9 +180,6 @@ def fix_cortex_a8: F<"fix-cortex-a8">,
 // is not complete.
 def require_cet: F<"require-cet">;
 
-def force_bti: F<"force-bti">,
-  HelpText<"Force enable AArch64 BTI in PLT, warn if Input ELF file does not have GNU_PROPERTY_AARCH64_FEATURE_1_BTI property">;
-
 defm format: Eq<"format", "Change the input format of the inputs following this option">,
   MetaVarName<"[default,elf,binary]">;
 
@@ -281,9 +278,6 @@ defm pack_dyn_relocs:
   Eq<"pack-dyn-relocs", "Pack dynamic relocations in the given format">,
   MetaVarName<"[none,android,relr,android+relr]">;
 
-def pac_plt: F<"pac-plt">,
-  HelpText<"AArch64 only, use pointer authentication in PLT">;
-
 defm use_android_relr_tags: B<"use-android-relr-tags",
     "Use SHT_ANDROID_RELR / DT_ANDROID_RELR* tags instead of SHT_RELR / DT_RELR*",
     "Use SHT_RELR / DT_RELR* tags (default)">;
diff --git a/lld/docs/ld.lld.1 b/lld/docs/ld.lld.1
index 5c558a4bcc7..7769cd03d50 100644
--- a/lld/docs/ld.lld.1
+++ b/lld/docs/ld.lld.1
@@ -191,8 +191,6 @@ Set the
 field to the specified value.
 .It Fl -fini Ns = Ns Ar symbol
 Specify a finalizer function.
-.It Fl -force-bti
-Force enable AArch64 BTI instruction in PLT, warn if Input ELF file does not have GNU_PROPERTY_AARCH64_FEATURE_1_BTI property.
 .It Fl -format Ns = Ns Ar input-format , Fl b Ar input-format
 Specify the format of the inputs following this option.
 .Ar input-format
@@ -401,8 +399,6 @@ If
 .Fl -use-android-relr-tags
 is specified, use SHT_ANDROID_RELR instead of SHT_RELR.
 .Pp
-.It Fl -pac-plt
-AArch64 only, use pointer authentication in PLT.
 .It Fl -pic-veneer
 Always generate position independent thunks.
 .It Fl -pie , Fl -pic-executable
@@ -599,6 +595,9 @@ Stack permissions are recorded in the
 .Dv PT_GNU_STACK
 segment.
 .Pp
+.It Cm force-bti
+Force enable AArch64 BTI instruction in PLT, warn if Input ELF file does not have GNU_PROPERTY_AARCH64_FEATURE_1_BTI property.
+.Pp
 .It Cm global
 Sets the
 .Dv DF_1_GLOBAL flag in the
@@ -688,6 +687,9 @@ flag to indicate that the object requires
 $ORIGIN
 processing.
 .Pp
+.It Cm pac-plt
+AArch64 only, use pointer authentication in PLT.
+.Pp
 .It Cm retpolineplt
 Emit retpoline format PLT entries as a mitigation for CVE-2017-5715.
 .Pp
diff --git a/lld/test/ELF/aarch64-bti-pac-cli-error.s b/lld/test/ELF/aarch64-bti-pac-cli-error.s
index 1ce7dde19db..f3ad7d14bbd 100644
--- a/lld/test/ELF/aarch64-bti-pac-cli-error.s
+++ b/lld/test/ELF/aarch64-bti-pac-cli-error.s
@@ -1,12 +1,12 @@
 # REQUIRES: x86
 # RUN: llvm-mc --triple=x86_64-pc-linux --filetype=obj -o %t.o %s
-# RUN: not ld.lld --pac-plt --force-bti %t.o -o %t 2>&1 | FileCheck %s
+# RUN: not ld.lld -z pac-plt -z force-bti %t.o -o %t 2>&1 | FileCheck %s
 #
-## Check that we error if --pac-plt and --force-bti are used when target is not
+## Check that we error if -z pac-plt and -z force-bti are used when target is not
 ## aarch64
 
-# CHECK: error: --pac-plt only supported on AArch64
-# CHECK-NEXT: error: --force-bti only supported on AArch64
+# CHECK: error: -z pac-plt only supported on AArch64
+# CHECK-NEXT: error: -z force-bti only supported on AArch64
 
         .globl start
 start:  ret
diff --git a/lld/test/ELF/aarch64-feature-bti.s b/lld/test/ELF/aarch64-feature-bti.s
index 0fa1cf83727..cbaf17b4d96 100644
--- a/lld/test/ELF/aarch64-feature-bti.s
+++ b/lld/test/ELF/aarch64-feature-bti.s
@@ -169,12 +169,12 @@
 # NOEX-NEXT:           add     x16, x16, #1032
 # NOEX-NEXT:           br      x17
 
-## Force BTI entries with the --force-bti command line option. Expect a warning
+## Force BTI entries with the -z force-bti command line option. Expect a warning
 ## from the file without the .note.gnu.property.
 
-# RUN: ld.lld %t.o %t2.o --force-bti %t.so -o %tforcebti.exe 2>&1 | FileCheck --check-prefix=FORCE-WARN %s
+# RUN: ld.lld %t.o %t2.o -z force-bti %t.so -o %tforcebti.exe 2>&1 | FileCheck --check-prefix=FORCE-WARN %s
 
-# FORCE-WARN: aarch64-feature-bti.s.tmp2.o: --force-bti: file does not have BTI property
+# FORCE-WARN: aarch64-feature-bti.s.tmp2.o: -z force-bti: file does not have BTI property
 
 
 # RUN: llvm-readelf -n %tforcebti.exe | FileCheck --check-prefix=BTIPROP %s
diff --git a/lld/test/ELF/aarch64-feature-btipac.s b/lld/test/ELF/aarch64-feature-btipac.s
index 30e00b2dbbd..17f8487f4d3 100644
--- a/lld/test/ELF/aarch64-feature-btipac.s
+++ b/lld/test/ELF/aarch64-feature-btipac.s
@@ -109,13 +109,13 @@
 # NODYN-NOT:   0x0000000070000001 (AARCH64_BTI_PLT)
 # NODYN-NOT:   0x0000000070000003 (AARCH64_PAC_PLT)
 
-## Check that combination of --pac-plt and --force-bti warns for the file that
+## Check that combination of -z pac-plt and -z force-bti warns for the file that
 ## doesn't contain the BTI property, but generates PAC and BTI PLT sequences.
-## The --pac-plt doesn't warn as it is not required for correctness.
+## The -z pac-plt doesn't warn as it is not required for correctness.
 
-# RUN: ld.lld %t.o %t3.o %t.so --pac-plt --force-bti -o %t.exe 2>&1 | FileCheck --check-prefix=FORCE-WARN %s
+# RUN: ld.lld %t.o %t3.o %t.so -z pac-plt -z force-bti -o %t.exe 2>&1 | FileCheck --check-prefix=FORCE-WARN %s
 
-# FORCE-WARN: aarch64-feature-btipac.s.tmp3.o: --force-bti: file does not have BTI property
+# FORCE-WARN: aarch64-feature-btipac.s.tmp3.o: -z force-bti: file does not have BTI property
 
 # RUN: llvm-readelf -n %t.exe | FileCheck --check-prefix=BTIPACPROP %s
 # RUN: llvm-objdump -d -mattr=+v8.5a --no-show-raw-insn %t.exe | FileCheck --check-prefix BTIPACEX %s
diff --git a/lld/test/ELF/aarch64-feature-pac.s b/lld/test/ELF/aarch64-feature-pac.s
index 7a4f8ee64ff..41c6cb69742 100644
--- a/lld/test/ELF/aarch64-feature-pac.s
+++ b/lld/test/ELF/aarch64-feature-pac.s
@@ -80,12 +80,12 @@
 # PACDYN-NOT:      0x0000000070000001 (AARCH64_BTI_PLT)
 # PACDYN:          0x0000000070000003 (AARCH64_PAC_PLT)
 
-## Turn on PAC entries with the --pac-plt command line option. There are no
+## Turn on PAC entries with the -z pac-plt command line option. There are no
 ## warnings in this case as the choice to use PAC in PLT entries is orthogonal
 ## to the choice of using PAC in relocatable objects. The presence of the PAC
 ## .note.gnu.property is an indication of preference by the relocatable object.
 
-# RUN: ld.lld %t.o %t2.o --pac-plt %t.so -o %tpacplt.exe
+# RUN: ld.lld %t.o %t2.o -z pac-plt %t.so -o %tpacplt.exe
 # RUN: llvm-readelf -n %tpacplt.exe | FileCheck --check-prefix=PACPROP %s
 # RUN: llvm-readelf --dynamic-table %tpacplt.exe | FileCheck --check-prefix PACDYN %s
 # RUN: llvm-objdump -d -mattr=+v8.3a --no-show-raw-insn %tpacplt.exe | FileCheck --check-prefix PACPLT %s