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Properly pass through the PIC mode to the integrated assembler when 

doing assembly-only, and unify the Driver's PIC argument parsing.

On a few architectures, parsing of assembly files annoyingly depends
on whether PIC is enabled or not. This was handled for external 'as'
already (passing -KPIC), but was missed for calls to the standalone
internal assembler.

The integrated-as.s test needed to be modified to not expect
-fsanitize=address to be unused, as now fsanitize *IS* used for
assembly, since -fsanitize=memory can sometimes imply -fPIE, which the
assembler needs to know (gack!!).

Differential Revision: http://reviews.llvm.org/D11845

llvm-svn: 245447
This commit is contained in:
James Y Knight 2015-08-19 15:12:02 +00:00
parent 61009142b8
commit 5bdf7ab0cf
3 changed files with 206 additions and 168 deletions
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5
clang/include/clang/Driver/CC1Options.td
View File

@ -146,7 +146,8 @@ def msave_temp_labels : Flag<["-"], "msave-temp-labels">,
HelpText<"Save temporary labels in the symbol table. "
"Note this may change .s semantics and shouldn't generally be used "
"on compiler-generated code.">;
def mrelocation_model : Separate<["-"], "mrelocation-model">,
HelpText<"The relocation model to use">;
}
def disable_llvm_optzns : Flag<["-"], "disable-llvm-optzns">,
@ -228,8 +229,6 @@ def backend_option : Separate<["-"], "backend-option">,
HelpText<"Additional arguments to forward to LLVM backend (during code gen)">;
def mregparm : Separate<["-"], "mregparm">,
HelpText<"Limit the number of registers available for integer arguments">;
def mrelocation_model : Separate<["-"], "mrelocation-model">,
HelpText<"The relocation model to use">;
def munwind_tables : Flag<["-"], "munwind-tables">,
HelpText<"Generate unwinding tables for all functions">;
def mconstructor_aliases : Flag<["-"], "mconstructor-aliases">,

363
clang/lib/Driver/Tools.cpp
View File

@ -32,7 +32,7 @@
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/TargetParser.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Support/Compression.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
@ -41,6 +41,7 @@
#include "llvm/Support/Process.h"
#include "llvm/Support/Program.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/TargetParser.h"
#ifdef LLVM_ON_UNIX
#include <unistd.h> // For getuid().
@ -51,21 +52,6 @@ using namespace clang::driver::tools;
using namespace clang;
using namespace llvm::opt;
static void addAssemblerKPIC(const ArgList &Args, ArgStringList &CmdArgs) {
Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
options::OPT_fpic, options::OPT_fno_pic,
options::OPT_fPIE, options::OPT_fno_PIE,
options::OPT_fpie, options::OPT_fno_pie);
if (!LastPICArg)
return;
if (LastPICArg->getOption().matches(options::OPT_fPIC) ||
LastPICArg->getOption().matches(options::OPT_fpic) ||
LastPICArg->getOption().matches(options::OPT_fPIE) ||
LastPICArg->getOption().matches(options::OPT_fpie)) {
CmdArgs.push_back("-KPIC");
}
}
/// CheckPreprocessingOptions - Perform some validation of preprocessing
/// arguments that is shared with gcc.
static void CheckPreprocessingOptions(const Driver &D, const ArgList &Args) {
@ -2939,6 +2925,159 @@ static void addPGOAndCoverageFlags(Compilation &C, const Driver &D,
}
}
/// Parses the various -fpic/-fPIC/-fpie/-fPIE arguments. Then,
/// smooshes them together with platform defaults, to decide whether
/// this compile should be using PIC mode or not. Returns a tuple of
/// (RelocationModel, PICLevel, IsPIE).
static std::tuple<llvm::Reloc::Model, unsigned, bool>
ParsePICArgs(const ToolChain &ToolChain, const llvm::Triple &Triple,
const ArgList &Args) {
// FIXME: why does this code...and so much everywhere else, use both
// ToolChain.getTriple() and Triple?
bool PIE = ToolChain.isPIEDefault();
bool PIC = PIE || ToolChain.isPICDefault();
bool IsPICLevelTwo = PIC;
bool KernelOrKext =
Args.hasArg(options::OPT_mkernel, options::OPT_fapple_kext);
// Android-specific defaults for PIC/PIE
if (ToolChain.getTriple().getEnvironment() == llvm::Triple::Android) {
switch (ToolChain.getArch()) {
case llvm::Triple::arm:
case llvm::Triple::armeb:
case llvm::Triple::thumb:
case llvm::Triple::thumbeb:
case llvm::Triple::aarch64:
case llvm::Triple::mips:
case llvm::Triple::mipsel:
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
PIC = true; // "-fpic"
break;
case llvm::Triple::x86:
case llvm::Triple::x86_64:
PIC = true; // "-fPIC"
IsPICLevelTwo = true;
break;
default:
break;
}
}
// OpenBSD-specific defaults for PIE
if (ToolChain.getTriple().getOS() == llvm::Triple::OpenBSD) {
switch (ToolChain.getArch()) {
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
case llvm::Triple::sparcel:
case llvm::Triple::x86:
case llvm::Triple::x86_64:
IsPICLevelTwo = false; // "-fpie"
break;
case llvm::Triple::ppc:
case llvm::Triple::sparc:
case llvm::Triple::sparcv9:
IsPICLevelTwo = true; // "-fPIE"
break;
default:
break;
}
}
// The last argument relating to either PIC or PIE wins, and no
// other argument is used. If the last argument is any flavor of the
// '-fno-...' arguments, both PIC and PIE are disabled. Any PIE
// option implicitly enables PIC at the same level.
Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
options::OPT_fpic, options::OPT_fno_pic,
options::OPT_fPIE, options::OPT_fno_PIE,
options::OPT_fpie, options::OPT_fno_pie);
// Check whether the tool chain trumps the PIC-ness decision. If the PIC-ness
// is forced, then neither PIC nor PIE flags will have no effect.
if (!ToolChain.isPICDefaultForced()) {
if (LastPICArg) {
Option O = LastPICArg->getOption();
if (O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic) ||
O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie)) {
PIE = O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie);
PIC =
PIE || O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic);
IsPICLevelTwo =
O.matches(options::OPT_fPIE) || O.matches(options::OPT_fPIC);
} else {
PIE = PIC = false;
}
}
}
// Introduce a Darwin-specific hack. If the default is PIC, but the
// PIC level would've been set to level 1, force it back to level 2
// PIC instead. This matches the behavior of Darwin GCC (based on
// chandlerc's informal testing in 2012).
if (PIC && ToolChain.getTriple().isOSDarwin())
IsPICLevelTwo |= ToolChain.isPICDefault();
// Note that these flags are trump-cards. Regardless of the order w.r.t. the
// PIC or PIE options above, if these show up, PIC is disabled.
if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6)))
PIC = PIE = false;
if (Args.hasArg(options::OPT_static))
PIC = PIE = false;
if (Arg *A = Args.getLastArg(options::OPT_mdynamic_no_pic)) {
// This is a very special mode. It trumps the other modes, almost no one
// uses it, and it isn't even valid on any OS but Darwin.
if (!ToolChain.getTriple().isOSDarwin())
ToolChain.getDriver().Diag(diag::err_drv_unsupported_opt_for_target)
<< A->getSpelling() << ToolChain.getTriple().str();
// FIXME: Warn when this flag trumps some other PIC or PIE flag.
// Only a forced PIC mode can cause the actual compile to have PIC defines
// etc., no flags are sufficient. This behavior was selected to closely
// match that of llvm-gcc and Apple GCC before that.
PIC = ToolChain.isPICDefault() && ToolChain.isPICDefaultForced();
return std::make_tuple(llvm::Reloc::DynamicNoPIC, PIC ? 2 : 0, false);
}
if (PIC)
return std::make_tuple(llvm::Reloc::PIC_, IsPICLevelTwo ? 2 : 1, PIE);
return std::make_tuple(llvm::Reloc::Static, 0, false);
}
static const char *RelocationModelName(llvm::Reloc::Model Model) {
switch (Model) {
case llvm::Reloc::Default:
return nullptr;
case llvm::Reloc::Static:
return "static";
case llvm::Reloc::PIC_:
return "pic";
case llvm::Reloc::DynamicNoPIC:
return "dynamic-no-pic";
}
assert(false && "Unknown Reloc::Model kind");
}
static void AddAssemblerKPIC(const ToolChain &ToolChain, const ArgList &Args,
ArgStringList &CmdArgs) {
llvm::Reloc::Model RelocationModel;
unsigned PICLevel;
bool IsPIE;
std::tie(RelocationModel, PICLevel, IsPIE) =
ParsePICArgs(ToolChain, ToolChain.getTriple(), Args);
if (RelocationModel != llvm::Reloc::Static)
CmdArgs.push_back("-KPIC");
}
void Clang::ConstructJob(Compilation &C, const JobAction &JA,
const InputInfo &Output, const InputInfoList &Inputs,
const ArgList &Args, const char *LinkingOutput) const {
@ -3137,134 +3276,23 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
CheckCodeGenerationOptions(D, Args);
bool PIE = getToolChain().isPIEDefault();
bool PIC = PIE || getToolChain().isPICDefault();
bool IsPICLevelTwo = PIC;
// Android-specific defaults for PIC/PIE
if (getToolChain().getTriple().getEnvironment() == llvm::Triple::Android) {
switch (getToolChain().getArch()) {
case llvm::Triple::arm:
case llvm::Triple::armeb:
case llvm::Triple::thumb:
case llvm::Triple::thumbeb:
case llvm::Triple::aarch64:
case llvm::Triple::mips:
case llvm::Triple::mipsel:
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
PIC = true; // "-fpic"
break;
case llvm::Triple::x86:
case llvm::Triple::x86_64:
PIC = true; // "-fPIC"
IsPICLevelTwo = true;
break;
default:
break;
}
}
// OpenBSD-specific defaults for PIE
if (getToolChain().getTriple().getOS() == llvm::Triple::OpenBSD) {
switch (getToolChain().getArch()) {
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
case llvm::Triple::sparcel:
case llvm::Triple::x86:
case llvm::Triple::x86_64:
IsPICLevelTwo = false; // "-fpie"
break;
case llvm::Triple::ppc:
case llvm::Triple::sparc:
case llvm::Triple::sparcv9:
IsPICLevelTwo = true; // "-fPIE"
break;
default:
break;
}
}
// For the PIC and PIE flag options, this logic is different from the
// legacy logic in very old versions of GCC, as that logic was just
// a bug no one had ever fixed. This logic is both more rational and
// consistent with GCC's new logic now that the bugs are fixed. The last
// argument relating to either PIC or PIE wins, and no other argument is
// used. If the last argument is any flavor of the '-fno-...' arguments,
// both PIC and PIE are disabled. Any PIE option implicitly enables PIC
// at the same level.
Arg *LastPICArg = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
options::OPT_fpic, options::OPT_fno_pic,
options::OPT_fPIE, options::OPT_fno_PIE,
options::OPT_fpie, options::OPT_fno_pie);
// Check whether the tool chain trumps the PIC-ness decision. If the PIC-ness
// is forced, then neither PIC nor PIE flags will have no effect.
if (!getToolChain().isPICDefaultForced()) {
if (LastPICArg) {
Option O = LastPICArg->getOption();
if (O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic) ||
O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie)) {
PIE = O.matches(options::OPT_fPIE) || O.matches(options::OPT_fpie);
PIC =
PIE || O.matches(options::OPT_fPIC) || O.matches(options::OPT_fpic);
IsPICLevelTwo =
O.matches(options::OPT_fPIE) || O.matches(options::OPT_fPIC);
} else {
PIE = PIC = false;
}
}
}
// Introduce a Darwin-specific hack. If the default is PIC but the flags
// specified while enabling PIC enabled level 1 PIC, just force it back to
// level 2 PIC instead. This matches the behavior of Darwin GCC (based on my
// informal testing).
if (PIC && getToolChain().getTriple().isOSDarwin())
IsPICLevelTwo |= getToolChain().isPICDefault();
// Note that these flags are trump-cards. Regardless of the order w.r.t. the
// PIC or PIE options above, if these show up, PIC is disabled.
if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6)))
PIC = PIE = false;
if (Args.hasArg(options::OPT_static))
PIC = PIE = false;
if (Arg *A = Args.getLastArg(options::OPT_mdynamic_no_pic)) {
// This is a very special mode. It trumps the other modes, almost no one
// uses it, and it isn't even valid on any OS but Darwin.
if (!getToolChain().getTriple().isOSDarwin())
D.Diag(diag::err_drv_unsupported_opt_for_target)
<< A->getSpelling() << getToolChain().getTriple().str();
// FIXME: Warn when this flag trumps some other PIC or PIE flag.
llvm::Reloc::Model RelocationModel;
unsigned PICLevel;
bool IsPIE;
std::tie(RelocationModel, PICLevel, IsPIE) =
ParsePICArgs(getToolChain(), Triple, Args);
const char *RMName = RelocationModelName(RelocationModel);
if (RMName) {
CmdArgs.push_back("-mrelocation-model");
CmdArgs.push_back("dynamic-no-pic");
// Only a forced PIC mode can cause the actual compile to have PIC defines
// etc., no flags are sufficient. This behavior was selected to closely
// match that of llvm-gcc and Apple GCC before that.
if (getToolChain().isPICDefault() && getToolChain().isPICDefaultForced()) {
CmdArgs.push_back("-pic-level");
CmdArgs.push_back("2");
}
} else {
// Currently, LLVM only knows about PIC vs. static; the PIE differences are
// handled in Clang's IRGen by the -pie-level flag.
CmdArgs.push_back("-mrelocation-model");
CmdArgs.push_back(PIC ? "pic" : "static");
if (PIC) {
CmdArgs.push_back("-pic-level");
CmdArgs.push_back(IsPICLevelTwo ? "2" : "1");
if (PIE) {
CmdArgs.push_back("-pie-level");
CmdArgs.push_back(IsPICLevelTwo ? "2" : "1");
}
CmdArgs.push_back(RMName);
}
if (PICLevel > 0) {
CmdArgs.push_back("-pic-level");
CmdArgs.push_back(PICLevel == 1 ? "1" : "2");
if (IsPIE) {
CmdArgs.push_back("-pie-level");
CmdArgs.push_back(PICLevel == 1 ? "1" : "2");
}
}
@ -5464,6 +5492,20 @@ void ClangAs::ConstructJob(Compilation &C, const JobAction &JA,
Args.AddAllArgs(CmdArgs, options::OPT_I);
}
// Handle -fPIC et al -- the relocation-model affects the assembler
// for some targets.
llvm::Reloc::Model RelocationModel;
unsigned PICLevel;
bool IsPIE;
std::tie(RelocationModel, PICLevel, IsPIE) =
ParsePICArgs(getToolChain(), Triple, Args);
const char *RMName = RelocationModelName(RelocationModel);
if (RMName) {
CmdArgs.push_back("-mrelocation-model");
CmdArgs.push_back(RMName);
}
// Optionally embed the -cc1as level arguments into the debug info, for build
// analysis.
if (getToolChain().UseDwarfDebugFlags()) {
@ -6926,7 +6968,7 @@ void openbsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
}
if (NeedsKPIC)
addAssemblerKPIC(Args, CmdArgs);
AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
@ -7233,7 +7275,7 @@ void freebsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
else
CmdArgs.push_back("-EL");
addAssemblerKPIC(Args, CmdArgs);
AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
} else if (getToolChain().getArch() == llvm::Triple::arm ||
getToolChain().getArch() == llvm::Triple::armeb ||
getToolChain().getArch() == llvm::Triple::thumb ||
@ -7266,7 +7308,7 @@ void freebsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
else
CmdArgs.push_back("-Av9a");
addAssemblerKPIC(Args, CmdArgs);
AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
}
Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);
@ -7510,20 +7552,20 @@ void netbsd::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
else
CmdArgs.push_back("-EL");
addAssemblerKPIC(Args, CmdArgs);
AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
break;
}
case llvm::Triple::sparc:
case llvm::Triple::sparcel:
CmdArgs.push_back("-32");
addAssemblerKPIC(Args, CmdArgs);
AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
break;
case llvm::Triple::sparcv9:
CmdArgs.push_back("-64");
CmdArgs.push_back("-Av9");
addAssemblerKPIC(Args, CmdArgs);
AddAssemblerKPIC(getToolChain(), Args, CmdArgs);
break;
default:
@ -7765,6 +7807,12 @@ void gnutools::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
ArgStringList CmdArgs;
bool NeedsKPIC = false;
llvm::Reloc::Model RelocationModel;
unsigned PICLevel;
bool IsPIE;
std::tie(RelocationModel, PICLevel, IsPIE) =
ParsePICArgs(getToolChain(), Triple, Args);
switch (getToolChain().getArch()) {
default:
break;
@ -7857,18 +7905,7 @@ void gnutools::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
// -mno-shared should be emitted unless -fpic, -fpie, -fPIC, -fPIE,
// or -mshared (not implemented) is in effect.
bool IsPicOrPie = false;
if (Arg *A = Args.getLastArg(options::OPT_fPIC, options::OPT_fno_PIC,
options::OPT_fpic, options::OPT_fno_pic,
options::OPT_fPIE, options::OPT_fno_PIE,
options::OPT_fpie, options::OPT_fno_pie)) {
if (A->getOption().matches(options::OPT_fPIC) ||
A->getOption().matches(options::OPT_fpic) ||
A->getOption().matches(options::OPT_fPIE) ||
A->getOption().matches(options::OPT_fpie))
IsPicOrPie = true;
}
if (!IsPicOrPie)
if (RelocationModel == llvm::Reloc::Static)
CmdArgs.push_back("-mno-shared");
// LLVM doesn't support -mplt yet and acts as if it is always given.
@ -7942,8 +7979,10 @@ void gnutools::Assembler::ConstructJob(Compilation &C, const JobAction &JA,
}
}
if (NeedsKPIC)
addAssemblerKPIC(Args, CmdArgs);
if (NeedsKPIC) {
if (RelocationModel != llvm::Reloc::Static)
CmdArgs.push_back("-KPIC");
}
Args.AddAllArgs(CmdArgs, options::OPT_I);
Args.AddAllArgValues(CmdArgs, options::OPT_Wa_COMMA, options::OPT_Xassembler);

6
clang/test/Driver/integrated-as.s
View File

@ -5,9 +5,6 @@
// RUN: %clang -### -c -integrated-as -Wa,-L %s 2>&1 | FileCheck --check-prefix=OPT_L %s
// OPT_L: msave-temp-labels
// RUN: %clang -### -target x86_64-linux-gnu -c -integrated-as %s -fsanitize=address 2>&1 %s | FileCheck --check-prefix=SANITIZE %s
// SANITIZE: argument unused during compilation: '-fsanitize=address'
// Test that -I params in -Wa, and -Xassembler args are passed to integrated assembler
// RUN: %clang -### -c -integrated-as %s -Wa,-I,foo_dir 2>&1 | FileCheck --check-prefix=WA_INCLUDE1 %s
// WA_INCLUDE1: cc1as
@ -46,3 +43,6 @@
// RUN: %clang -### -x assembler -c -integrated-as %s -I myincludedir 2>&1 | FileCheck --check-prefix=INCLUDEPATH %s
// INCLUDEPATH: "-I" "myincludedir"
// RUN: %clang -### -x assembler -c -fPIC -integrated-as %s 2>&1 | FileCheck --check-prefix=PIC %s
// PIC: "-mrelocation-model" "pic"