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Teach Clang about PIE compilations. This is the first step of PR12380. 

First, this patch cleans up the parsing of the PIC and PIE family of
options in the driver. The existing logic failed to claim arguments all
over the place resulting in kludges that marked the options as unused.
Instead actually walk all of the arguments and claim them properly.

We now treat -f{,no-}{pic,PIC,pie,PIE} as a single set, accepting the
last one on the commandline. Previously there were lots of ordering bugs
that could creep in due to the nature of the parsing. Let me know if
folks would like weird things such as "-fPIE -fno-pic" to turn on PIE,
but disable full PIC. This doesn't make any sense to me, but we could in
theory support it.

Options that seem to have intentional "trump" status (-static, -mkernel,
etc) continue to do so and are commented as such.

Next, a -pie-level flag is threaded into the frontend, rigged to
a language option, and handled preprocessor, setting up the appropriate
defines. We'll now have the correct defines when compiling with -fpie.

The one place outside of the preprocessor that was inspecting the PIC
level (as opposed to the relocation model, which is set and handled
separately, yay!) is in the GNU ObjC runtime. I changed it to exactly
preserve existing behavior. If folks want to change its behavior in the
face of PIE, they can do that in a separate patch.

Essentially the only functionality changed here is the preprocessor
defines and bug-fixes to the argument management.

Tests have been updated and extended to test all of this a bit more
thoroughly.

llvm-svn: 154291
This commit is contained in:
Chandler Carruth 2012-04-08 16:40:35 +00:00
parent 4e97337914
commit c0c0455f55
10 changed files with 168 additions and 30 deletions
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3
clang/include/clang/Basic/LangOptions.def
View File

@ -96,7 +96,8 @@ LANGOPT(OptimizeSize , 1, 0, "__OPTIMIZE_SIZE__ predefined macro")
LANGOPT(Static , 1, 0, "__STATIC__ predefined macro (as opposed to __DYNAMIC__)")
VALUE_LANGOPT(PackStruct , 32, 0,
"default struct packing maximum alignment")
VALUE_LANGOPT(PICLevel , 2, 0, "__PIC__ level")
VALUE_LANGOPT(PICLevel , 2, 0, "__PIC__ level")
VALUE_LANGOPT(PIELevel , 2, 0, "__PIE__ level")
LANGOPT(GNUInline , 1, 0, "GNU inline semantics")
LANGOPT(NoInlineDefine , 1, 0, "__NO_INLINE__ predefined macro")
LANGOPT(Deprecated , 1, 0, "__DEPRECATED predefined macro")

2
clang/include/clang/Driver/CC1Options.td
View File

@ -632,6 +632,8 @@ def fwrapv : Flag<"-fwrapv">,
HelpText<"Treat signed integer overflow as two's complement">;
def pic_level : Separate<"-pic-level">,
HelpText<"Value for __PIC__">;
def pie_level : Separate<"-pie-level">,
HelpText<"Value for __PIE__">;
def pthread : Flag<"-pthread">,
HelpText<"Support POSIX threads in generated code">;
def fpack_struct : Separate<"-fpack-struct">,

10
clang/include/clang/Driver/Options.td
View File

@ -265,8 +265,8 @@ def exported__symbols__list : Separate<"-exported_symbols_list">;
def e : JoinedOrSeparate<"-e">;
def fPIC : Flag<"-fPIC">, Group<f_Group>;
def fno_PIC : Flag<"-fno-PIC">, Group<f_Group>;
def fPIE : Flag<"-fPIE">, Group<f_Group>, Flags<[NoArgumentUnused]>;
def fno_PIE : Flag<"-fno-PIE">, Group<f_Group>, Flags<[NoArgumentUnused]>;
def fPIE : Flag<"-fPIE">, Group<f_Group>;
def fno_PIE : Flag<"-fno-PIE">, Group<f_Group>;
def faccess_control : Flag<"-faccess-control">, Group<f_Group>;
def fallow_unsupported : Flag<"-fallow-unsupported">, Group<f_Group>;
def faltivec : Flag<"-faltivec">, Group<f_Group>;
@ -499,8 +499,8 @@ def fpascal_strings : Flag<"-fpascal-strings">, Group<f_Group>;
def fpch_preprocess : Flag<"-fpch-preprocess">, Group<f_Group>;
def fpic : Flag<"-fpic">, Group<f_Group>;
def fno_pic : Flag<"-fno-pic">, Group<f_Group>;
def fpie : Flag<"-fpie">, Group<f_Group>, Flags<[NoArgumentUnused]>;
def fno_pie : Flag<"-fno-pie">, Group<f_Group>, Flags<[NoArgumentUnused]>;
def fpie : Flag<"-fpie">, Group<f_Group>;
def fno_pie : Flag<"-fno-pie">, Group<f_Group>;
def fprofile_arcs : Flag<"-fprofile-arcs">, Group<f_Group>;
def fprofile_generate : Flag<"-fprofile-generate">, Group<f_Group>;
def framework : Separate<"-framework">, Flags<[LinkerInput]>;
@ -605,7 +605,7 @@ def march_EQ : Joined<"-march=">, Group<m_Group>;
def mcmodel_EQ : Joined<"-mcmodel=">, Group<m_Group>;
def mconstant_cfstrings : Flag<"-mconstant-cfstrings">, Group<clang_ignored_m_Group>;
def mcpu_EQ : Joined<"-mcpu=">, Group<m_Group>;
def mdynamic_no_pic : Joined<"-mdynamic-no-pic">, Group<m_Group>, Flags<[NoArgumentUnused]>;
def mdynamic_no_pic : Joined<"-mdynamic-no-pic">, Group<m_Group>;
def mfix_and_continue : Flag<"-mfix-and-continue">, Group<clang_ignored_m_Group>;
def mfloat_abi_EQ : Joined<"-mfloat-abi=">, Group<m_Group>;
def mfpmath_EQ : Joined<"-mfpmath=">, Group<m_Group>;

2
clang/lib/CodeGen/CGObjCGNU.cpp
View File

@ -2594,7 +2594,7 @@ llvm::GlobalVariable *CGObjCGNU::ObjCIvarOffsetVariable(
// to replace it with the real version for a library. In non-PIC code you
// must compile with the fragile ABI if you want to use ivars from a
// GCC-compiled class.
if (CGM.getLangOpts().PICLevel) {
if (CGM.getLangOpts().PICLevel || CGM.getLangOpts().PIELevel) {
llvm::GlobalVariable *IvarOffsetGV = new llvm::GlobalVariable(TheModule,
Int32Ty, false,
llvm::GlobalValue::PrivateLinkage, OffsetGuess, Name+".guess");

66
clang/lib/Driver/Tools.cpp
View File

@ -1480,19 +1480,43 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
// would do to enable flag_pic.
//
// FIXME: Centralize this code.
bool PICEnabled = (Args.hasArg(options::OPT_fPIC) ||
Args.hasArg(options::OPT_fpic) ||
Args.hasArg(options::OPT_fPIE) ||
Args.hasArg(options::OPT_fpie));
bool PICDisabled = (Args.hasArg(options::OPT_mkernel) ||
Args.hasArg(options::OPT_static) ||
Args.hasArg(options::OPT_fno_PIC) ||
Args.hasArg(options::OPT_fno_pic) ||
Args.hasArg(options::OPT_fno_PIE) ||
Args.hasArg(options::OPT_fno_pie));
Arg *LastPICArg = 0;
for (ArgList::const_iterator I = Args.begin(), E = Args.end(); I != E; ++I) {
if ((*I)->getOption().matches(options::OPT_fPIC) ||
(*I)->getOption().matches(options::OPT_fno_PIC) ||
(*I)->getOption().matches(options::OPT_fpic) ||
(*I)->getOption().matches(options::OPT_fno_pic) ||
(*I)->getOption().matches(options::OPT_fPIE) ||
(*I)->getOption().matches(options::OPT_fno_PIE) ||
(*I)->getOption().matches(options::OPT_fpie) ||
(*I)->getOption().matches(options::OPT_fno_pie)) {
LastPICArg = *I;
(*I)->claim();
}
}
bool PICDisabled = false;
bool PICEnabled = false;
bool PICForPIE = false;
if (LastPICArg) {
PICForPIE = (LastPICArg->getOption().matches(options::OPT_fPIE) ||
LastPICArg->getOption().matches(options::OPT_fpie));
PICEnabled = (PICForPIE ||
LastPICArg->getOption().matches(options::OPT_fPIC) ||
LastPICArg->getOption().matches(options::OPT_fpic));
PICDisabled = !PICEnabled;
}
// 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 (Args.hasArg(options::OPT_mkernel))
PICDisabled = true;
if (Args.hasArg(options::OPT_static))
PICDisabled = true;
bool DynamicNoPIC = Args.hasArg(options::OPT_mdynamic_no_pic);
// Select the relocation model.
const char *Model = getToolChain().GetForcedPicModel();
if (!Model) {
if (Args.hasArg(options::OPT_mdynamic_no_pic))
if (DynamicNoPIC)
Model = "dynamic-no-pic";
else if (PICDisabled)
Model = "static";
@ -1501,19 +1525,25 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
else
Model = getToolChain().GetDefaultRelocationModel();
}
if (StringRef(Model) != "pic") {
StringRef ModelStr = Model ? Model : "";
if (Model && ModelStr != "pic") {
CmdArgs.push_back("-mrelocation-model");
CmdArgs.push_back(Model);
}
// Infer the __PIC__ value.
//
// FIXME: This isn't quite right on Darwin, which always sets
// __PIC__=2.
if (strcmp(Model, "pic") == 0 || strcmp(Model, "dynamic-no-pic") == 0) {
// Infer the __PIC__ and __PIE__ values.
if (ModelStr == "pic" && PICForPIE) {
CmdArgs.push_back("-pie-level");
CmdArgs.push_back((LastPICArg &&
LastPICArg->getOption().matches(options::OPT_fPIE)) ?
"2" : "1");
} else if (ModelStr == "pic" || ModelStr == "dynamic-no-pic") {
CmdArgs.push_back("-pic-level");
CmdArgs.push_back(Args.hasArg(options::OPT_fPIC) ? "2" : "1");
CmdArgs.push_back(((ModelStr != "dynamic-no-pic" && LastPICArg &&
LastPICArg->getOption().matches(options::OPT_fPIC)) ||
getToolChain().getTriple().isOSDarwin()) ? "2" : "1");
}
if (!Args.hasFlag(options::OPT_fmerge_all_constants,
options::OPT_fno_merge_all_constants))
CmdArgs.push_back("-fno-merge-all-constants");

3
clang/lib/Frontend/CompilerInvocation.cpp
View File

@ -740,6 +740,8 @@ static void LangOptsToArgs(const LangOptions &Opts, ToArgsList &Res) {
Res.push_back("-fno-bitfield-type-alignment");
if (Opts.PICLevel)
Res.push_back("-pic-level", llvm::utostr(Opts.PICLevel));
if (Opts.PIELevel)
Res.push_back("-pie-level", llvm::utostr(Opts.PIELevel));
if (Opts.ObjCGCBitmapPrint)
Res.push_back("-print-ivar-layout");
if (Opts.NoConstantCFStrings)
@ -1897,6 +1899,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
Opts.EmitAllDecls = Args.hasArg(OPT_femit_all_decls);
Opts.PackStruct = Args.getLastArgIntValue(OPT_fpack_struct, 0, Diags);
Opts.PICLevel = Args.getLastArgIntValue(OPT_pic_level, 0, Diags);
Opts.PIELevel = Args.getLastArgIntValue(OPT_pie_level, 0, Diags);
Opts.Static = Args.hasArg(OPT_static_define);
Opts.DumpRecordLayoutsSimple = Args.hasArg(OPT_fdump_record_layouts_simple);
Opts.DumpRecordLayouts = Opts.DumpRecordLayoutsSimple

4
clang/lib/Frontend/InitPreprocessor.cpp
View File

@ -528,6 +528,10 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
Builder.defineMacro("__PIC__", Twine(PICLevel));
Builder.defineMacro("__pic__", Twine(PICLevel));
}
if (unsigned PIELevel = LangOpts.PIELevel) {
Builder.defineMacro("__PIE__", Twine(PIELevel));
Builder.defineMacro("__pie__", Twine(PIELevel));
}
// Macros to control C99 numerics and <float.h>
Builder.defineMacro("__FLT_EVAL_METHOD__", Twine(TI.getFloatEvalMethod()));

5
clang/test/Driver/fno-pic.c
View File

@ -1,5 +0,0 @@
// RUN: %clang -c %s -target i386-apple-darwin -### 2>&1 | FileCheck %s --check-prefix=PIC_ON_BY_DEFAULT
// PIC_ON_BY_DEFAULT: "-pic-level" "1"
// RUN: %clang -c %s -target i386-apple-darwin -### -fno-pic 2>&1 | FileCheck %s --check-prefix=FNO_PIC
// FNO_PIC: "-mrelocation-model" "static"

81
clang/test/Driver/pic.c Normal file
View File

@ -0,0 +1,81 @@
// Test the driver's control over the PIC behavior. These consist of tests of
// the relocation model flags and the pic level flags passed to CC1.
//
// CHECK-NO-PIC: "-mrelocation-model" "static"
// CHECK-NO-PIC-NOT: "-pic-level"
// CHECK-NO-PIC-NOT: "-pie-level"
//
// CHECK-DYNAMIC-NO-PIC1: "-mrelocation-model" "dynamic-no-pic"
// CHECK-DYNAMIC-NO-PIC1: "-pic-level" "1"
//
// CHECK-DYNAMIC-NO-PIC2: "-mrelocation-model" "dynamic-no-pic"
// CHECK-DYNAMIC-NO-PIC2: "-pic-level" "2"
//
// CHECK-PIC1-NOT: "-mrelocation-model"
// CHECK-PIC1: "-pic-level" "1"
//
// CHECK-PIC2-NOT: "-mrelocation-model"
// CHECK-PIC2: "-pic-level" "2"
//
// CHECK-PIE1-NOT: "-mrelocation-model"
// CHECK-PIE1: "-pie-level" "1"
//
// CHECK-PIE2-NOT: "-mrelocation-model"
// CHECK-PIE2: "-pie-level" "2"
//
// RUN: %clang -c %s -target i386-unknown-unknown -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIC1
// RUN: %clang -c %s -target i386-unknown-unknown -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIC2
// RUN: %clang -c %s -target i386-unknown-unknown -fpie -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIE1
// RUN: %clang -c %s -target i386-unknown-unknown -fPIE -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIE2
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -fno-pic -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fPIC -fno-PIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -fno-PIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fPIC -fno-pic -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpie -fno-pie -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fPIE -fno-PIE -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpie -fno-PIE -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fPIE -fno-pie -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpie -fno-pic -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -fno-pie -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIC2
// RUN: %clang -c %s -target i386-unknown-unknown -fPIC -fpic -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIC1
// RUN: %clang -c %s -target i386-unknown-unknown -fpic -fPIE -fpie -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIE1
// RUN: %clang -c %s -target i386-unknown-unknown -fpie -fPIC -fPIE -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIE2
//
// Defaults change for Darwin.
// RUN: %clang -c %s -target i386-apple-darwin -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-PIC2
// RUN: %clang -c %s -target i386-apple-darwin -fno-pic -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-apple-darwin -fno-PIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
//
// Disregard any of the PIC-specific flags if we have a trump-card flag.
// RUN: %clang -c %s -target i386-unknown-unknown -mkernel -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -static -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-NO-PIC
// RUN: %clang -c %s -target i386-unknown-unknown -mdynamic-no-pic -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-DYNAMIC-NO-PIC1
// RUN: %clang -c %s -target i386-apple-darwin -mdynamic-no-pic -fPIC -### 2>&1 \
// RUN: | FileCheck %s --check-prefix=CHECK-DYNAMIC-NO-PIC2

22
clang/test/Preprocessor/pic.c
View File

@ -1,12 +1,34 @@
// RUN: %clang_cc1 -dM -E -o - %s \
// RUN: | FileCheck %s
// CHECK-NOT: #define __PIC__
// CHECK-NOT: #define __PIE__
// CHECK-NOT: #define __pic__
// CHECK-NOT: #define __pie__
//
// RUN: %clang_cc1 -pic-level 1 -dM -E -o - %s \
// RUN: | FileCheck --check-prefix=CHECK-PIC1 %s
// CHECK-PIC1: #define __PIC__ 1
// CHECK-PIC1-NOT: #define __PIE__
// CHECK-PIC1: #define __pic__ 1
// CHECK-PIC1-NOT: #define __pie__
//
// RUN: %clang_cc1 -pic-level 2 -dM -E -o - %s \
// RUN: | FileCheck --check-prefix=CHECK-PIC2 %s
// CHECK-PIC2: #define __PIC__ 2
// CHECK-PIC2-NOT: #define __PIE__
// CHECK-PIC2: #define __pic__ 2
// CHECK-PIC2-NOT: #define __pie__
//
// RUN: %clang_cc1 -pie-level 1 -dM -E -o - %s \
// RUN: | FileCheck --check-prefix=CHECK-PIE1 %s
// CHECK-PIE1-NOT: #define __PIC__
// CHECK-PIE1: #define __PIE__ 1
// CHECK-PIE1-NOT: #define __pic__
// CHECK-PIE1: #define __pie__ 1
//
// RUN: %clang_cc1 -pie-level 2 -dM -E -o - %s \
// RUN: | FileCheck --check-prefix=CHECK-PIE2 %s
// CHECK-PIE2-NOT: #define __PIC__
// CHECK-PIE2: #define __PIE__ 2
// CHECK-PIE2-NOT: #define __pic__
// CHECK-PIE2: #define __pie__ 2