TargetInfo.h revision 686775deca8b8685eb90801495880e3abdd844c2 
1//===--- TargetInfo.h - Expose information about the target -----*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file defines the TargetInfo interface.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_BASIC_TARGETINFO_H
15#define LLVM_CLANG_BASIC_TARGETINFO_H
16
17#include "clang/Basic/LLVM.h"
18#include "llvm/ADT/IntrusiveRefCntPtr.h"
19#include "llvm/ADT/StringMap.h"
20#include "llvm/ADT/StringRef.h"
21#include "llvm/ADT/StringSwitch.h"
22#include "llvm/ADT/Triple.h"
23#include "llvm/Support/DataTypes.h"
24#include "clang/Basic/AddressSpaces.h"
25#include "clang/Basic/VersionTuple.h"
26#include <cassert>
27#include <vector>
28#include <string>
29
30namespace llvm {
31struct fltSemantics;
32}
33
34namespace clang {
35class Diagnostic;
36class LangOptions;
37class MacroBuilder;
38class SourceLocation;
39class SourceManager;
40class TargetOptions;
41
42namespace Builtin { struct Info; }
43
44/// TargetCXXABI - The types of C++ ABIs for which we can generate code.
45enum TargetCXXABI {
46  /// The generic ("Itanium") C++ ABI, documented at:
47  ///   http://www.codesourcery.com/public/cxx-abi/
48  CXXABI_Itanium,
49
50  /// The ARM C++ ABI, based largely on the Itanium ABI but with
51  /// significant differences.
52  ///    http://infocenter.arm.com
53  ///                    /help/topic/com.arm.doc.ihi0041c/IHI0041C_cppabi.pdf
54  CXXABI_ARM,
55
56  /// The Visual Studio ABI.  Only scattered official documentation exists.
57  CXXABI_Microsoft
58};
59
60/// TargetInfo - This class exposes information about the current target.
61///
62class TargetInfo : public llvm::RefCountedBase<TargetInfo> {
63  llvm::Triple Triple;
64protected:
65  // Target values set by the ctor of the actual target implementation.  Default
66  // values are specified by the TargetInfo constructor.
67  bool TLSSupported;
68  bool NoAsmVariants;  // True if {|} are normal characters.
69  unsigned char PointerWidth, PointerAlign;
70  unsigned char BoolWidth, BoolAlign;
71  unsigned char IntWidth, IntAlign;
72  unsigned char FloatWidth, FloatAlign;
73  unsigned char DoubleWidth, DoubleAlign;
74  unsigned char LongDoubleWidth, LongDoubleAlign;
75  unsigned char LargeArrayMinWidth, LargeArrayAlign;
76  unsigned char LongWidth, LongAlign;
77  unsigned char LongLongWidth, LongLongAlign;
78  const char *DescriptionString;
79  const char *UserLabelPrefix;
80  const char *MCountName;
81  const llvm::fltSemantics *FloatFormat, *DoubleFormat, *LongDoubleFormat;
82  unsigned char RegParmMax, SSERegParmMax;
83  TargetCXXABI CXXABI;
84  const LangAS::Map *AddrSpaceMap;
85
86  mutable StringRef PlatformName;
87  mutable VersionTuple PlatformMinVersion;
88
89  unsigned HasAlignMac68kSupport : 1;
90  unsigned RealTypeUsesObjCFPRet : 3;
91
92  // TargetInfo Constructor.  Default initializes all fields.
93  TargetInfo(const std::string &T);
94
95public:
96  /// CreateTargetInfo - Construct a target for the given options.
97  ///
98  /// \param Opts - The options to use to initialize the target. The target may
99  /// modify the options to canonicalize the target feature information to match
100  /// what the backend expects.
101  static TargetInfo* CreateTargetInfo(Diagnostic &Diags, TargetOptions &Opts);
102
103  virtual ~TargetInfo();
104
105  ///===---- Target Data Type Query Methods -------------------------------===//
106  enum IntType {
107    NoInt = 0,
108    SignedShort,
109    UnsignedShort,
110    SignedInt,
111    UnsignedInt,
112    SignedLong,
113    UnsignedLong,
114    SignedLongLong,
115    UnsignedLongLong
116  };
117
118  enum RealType {
119    Float = 0,
120    Double,
121    LongDouble
122  };
123
124protected:
125  IntType SizeType, IntMaxType, UIntMaxType, PtrDiffType, IntPtrType, WCharType,
126          WIntType, Char16Type, Char32Type, Int64Type, SigAtomicType;
127
128  /// Control whether the alignment of bit-field types is respected when laying
129  /// out structures. If true, then the alignment of the bit-field type will be
130  /// used to (a) impact the alignment of the containing structure, and (b)
131  /// ensure that the individual bit-field will not straddle an alignment
132  /// boundary.
133  unsigned UseBitFieldTypeAlignment : 1;
134
135public:
136  IntType getSizeType() const { return SizeType; }
137  IntType getIntMaxType() const { return IntMaxType; }
138  IntType getUIntMaxType() const { return UIntMaxType; }
139  IntType getPtrDiffType(unsigned AddrSpace) const {
140    return AddrSpace == 0 ? PtrDiffType : getPtrDiffTypeV(AddrSpace);
141  }
142  IntType getIntPtrType() const { return IntPtrType; }
143  IntType getWCharType() const { return WCharType; }
144  IntType getWIntType() const { return WIntType; }
145  IntType getChar16Type() const { return Char16Type; }
146  IntType getChar32Type() const { return Char32Type; }
147  IntType getInt64Type() const { return Int64Type; }
148  IntType getSigAtomicType() const { return SigAtomicType; }
149
150
151  /// getTypeWidth - Return the width (in bits) of the specified integer type
152  /// enum. For example, SignedInt -> getIntWidth().
153  unsigned getTypeWidth(IntType T) const;
154
155  /// getTypeAlign - Return the alignment (in bits) of the specified integer
156  /// type enum. For example, SignedInt -> getIntAlign().
157  unsigned getTypeAlign(IntType T) const;
158
159  /// isTypeSigned - Return whether an integer types is signed. Returns true if
160  /// the type is signed; false otherwise.
161  static bool isTypeSigned(IntType T);
162
163  /// getPointerWidth - Return the width of pointers on this target, for the
164  /// specified address space.
165  uint64_t getPointerWidth(unsigned AddrSpace) const {
166    return AddrSpace == 0 ? PointerWidth : getPointerWidthV(AddrSpace);
167  }
168  uint64_t getPointerAlign(unsigned AddrSpace) const {
169    return AddrSpace == 0 ? PointerAlign : getPointerAlignV(AddrSpace);
170  }
171
172  /// getBoolWidth/Align - Return the size of '_Bool' and C++ 'bool' for this
173  /// target, in bits.
174  unsigned getBoolWidth() const { return BoolWidth; }
175  unsigned getBoolAlign() const { return BoolAlign; }
176
177  unsigned getCharWidth() const { return 8; } // FIXME
178  unsigned getCharAlign() const { return 8; } // FIXME
179
180  /// getShortWidth/Align - Return the size of 'signed short' and
181  /// 'unsigned short' for this target, in bits.
182  unsigned getShortWidth() const { return 16; } // FIXME
183  unsigned getShortAlign() const { return 16; } // FIXME
184
185  /// getIntWidth/Align - Return the size of 'signed int' and 'unsigned int' for
186  /// this target, in bits.
187  unsigned getIntWidth() const { return IntWidth; }
188  unsigned getIntAlign() const { return IntAlign; }
189
190  /// getLongWidth/Align - Return the size of 'signed long' and 'unsigned long'
191  /// for this target, in bits.
192  unsigned getLongWidth() const { return LongWidth; }
193  unsigned getLongAlign() const { return LongAlign; }
194
195  /// getLongLongWidth/Align - Return the size of 'signed long long' and
196  /// 'unsigned long long' for this target, in bits.
197  unsigned getLongLongWidth() const { return LongLongWidth; }
198  unsigned getLongLongAlign() const { return LongLongAlign; }
199
200  /// getWCharWidth/Align - Return the size of 'wchar_t' for this target, in
201  /// bits.
202  unsigned getWCharWidth() const { return getTypeWidth(WCharType); }
203  unsigned getWCharAlign() const { return getTypeAlign(WCharType); }
204
205  /// getChar16Width/Align - Return the size of 'char16_t' for this target, in
206  /// bits.
207  unsigned getChar16Width() const { return getTypeWidth(Char16Type); }
208  unsigned getChar16Align() const { return getTypeAlign(Char16Type); }
209
210  /// getChar32Width/Align - Return the size of 'char32_t' for this target, in
211  /// bits.
212  unsigned getChar32Width() const { return getTypeWidth(Char32Type); }
213  unsigned getChar32Align() const { return getTypeAlign(Char32Type); }
214
215  /// getFloatWidth/Align/Format - Return the size/align/format of 'float'.
216  unsigned getFloatWidth() const { return FloatWidth; }
217  unsigned getFloatAlign() const { return FloatAlign; }
218  const llvm::fltSemantics &getFloatFormat() const { return *FloatFormat; }
219
220  /// getDoubleWidth/Align/Format - Return the size/align/format of 'double'.
221  unsigned getDoubleWidth() const { return DoubleWidth; }
222  unsigned getDoubleAlign() const { return DoubleAlign; }
223  const llvm::fltSemantics &getDoubleFormat() const { return *DoubleFormat; }
224
225  /// getLongDoubleWidth/Align/Format - Return the size/align/format of 'long
226  /// double'.
227  unsigned getLongDoubleWidth() const { return LongDoubleWidth; }
228  unsigned getLongDoubleAlign() const { return LongDoubleAlign; }
229  const llvm::fltSemantics &getLongDoubleFormat() const {
230    return *LongDoubleFormat;
231  }
232
233  // getLargeArrayMinWidth/Align - Return the minimum array size that is
234  // 'large' and its alignment.
235  unsigned getLargeArrayMinWidth() const { return LargeArrayMinWidth; }
236  unsigned getLargeArrayAlign() const { return LargeArrayAlign; }
237
238  /// getIntMaxTWidth - Return the size of intmax_t and uintmax_t for this
239  /// target, in bits.
240  unsigned getIntMaxTWidth() const {
241    return getTypeWidth(IntMaxType);
242  }
243
244  /// getRegisterWidth - Return the "preferred" register width on this target.
245  uint64_t getRegisterWidth() const {
246    // Currently we assume the register width on the target matches the pointer
247    // width, we can introduce a new variable for this if/when some target wants
248    // it.
249    return LongWidth;
250  }
251
252  /// getUserLabelPrefix - This returns the default value of the
253  /// __USER_LABEL_PREFIX__ macro, which is the prefix given to user symbols by
254  /// default.  On most platforms this is "_", but it is "" on some, and "." on
255  /// others.
256  const char *getUserLabelPrefix() const {
257    return UserLabelPrefix;
258  }
259
260  /// MCountName - This returns name of the mcount instrumentation function.
261  const char *getMCountName() const {
262    return MCountName;
263  }
264
265  bool useBitFieldTypeAlignment() const {
266    return UseBitFieldTypeAlignment;
267  }
268
269  /// hasAlignMac68kSupport - Check whether this target support '#pragma options
270  /// align=mac68k'.
271  bool hasAlignMac68kSupport() const {
272    return HasAlignMac68kSupport;
273  }
274
275  /// getTypeName - Return the user string for the specified integer type enum.
276  /// For example, SignedShort -> "short".
277  static const char *getTypeName(IntType T);
278
279  /// getTypeConstantSuffix - Return the constant suffix for the specified
280  /// integer type enum. For example, SignedLong -> "L".
281  static const char *getTypeConstantSuffix(IntType T);
282
283  /// \brief Check whether the given real type should use the "fpret" flavor of
284  /// Obj-C message passing on this target.
285  bool useObjCFPRetForRealType(RealType T) const {
286    return RealTypeUsesObjCFPRet & (1 << T);
287  }
288
289  ///===---- Other target property query methods --------------------------===//
290
291  /// getTargetDefines - Appends the target-specific #define values for this
292  /// target set to the specified buffer.
293  virtual void getTargetDefines(const LangOptions &Opts,
294                                MacroBuilder &Builder) const = 0;
295
296
297  /// getTargetBuiltins - Return information about target-specific builtins for
298  /// the current primary target, and info about which builtins are non-portable
299  /// across the current set of primary and secondary targets.
300  virtual void getTargetBuiltins(const Builtin::Info *&Records,
301                                 unsigned &NumRecords) const = 0;
302
303  /// getVAListDeclaration - Return the declaration to use for
304  /// __builtin_va_list, which is target-specific.
305  virtual const char *getVAListDeclaration() const = 0;
306
307  /// isValidClobber - Returns whether the passed in string is
308  /// a valid clobber in an inline asm statement. This is used by
309  /// Sema.
310  bool isValidClobber(StringRef Name) const;
311
312  /// isValidGCCRegisterName - Returns whether the passed in string
313  /// is a valid register name according to GCC. This is used by Sema for
314  /// inline asm statements.
315  bool isValidGCCRegisterName(StringRef Name) const;
316
317  // getNormalizedGCCRegisterName - Returns the "normalized" GCC register name.
318  // For example, on x86 it will return "ax" when "eax" is passed in.
319  StringRef getNormalizedGCCRegisterName(StringRef Name) const;
320
321  struct ConstraintInfo {
322    enum {
323      CI_None = 0x00,
324      CI_AllowsMemory = 0x01,
325      CI_AllowsRegister = 0x02,
326      CI_ReadWrite = 0x04,       // "+r" output constraint (read and write).
327      CI_HasMatchingInput = 0x08 // This output operand has a matching input.
328    };
329    unsigned Flags;
330    int TiedOperand;
331
332    std::string ConstraintStr;  // constraint: "=rm"
333    std::string Name;           // Operand name: [foo] with no []'s.
334  public:
335    ConstraintInfo(StringRef ConstraintStr, StringRef Name)
336      : Flags(0), TiedOperand(-1), ConstraintStr(ConstraintStr.str()),
337      Name(Name.str()) {}
338
339    const std::string &getConstraintStr() const { return ConstraintStr; }
340    const std::string &getName() const { return Name; }
341    bool isReadWrite() const { return (Flags & CI_ReadWrite) != 0; }
342    bool allowsRegister() const { return (Flags & CI_AllowsRegister) != 0; }
343    bool allowsMemory() const { return (Flags & CI_AllowsMemory) != 0; }
344
345    /// hasMatchingInput - Return true if this output operand has a matching
346    /// (tied) input operand.
347    bool hasMatchingInput() const { return (Flags & CI_HasMatchingInput) != 0; }
348
349    /// hasTiedOperand() - Return true if this input operand is a matching
350    /// constraint that ties it to an output operand.  If this returns true,
351    /// then getTiedOperand will indicate which output operand this is tied to.
352    bool hasTiedOperand() const { return TiedOperand != -1; }
353    unsigned getTiedOperand() const {
354      assert(hasTiedOperand() && "Has no tied operand!");
355      return (unsigned)TiedOperand;
356    }
357
358    void setIsReadWrite() { Flags |= CI_ReadWrite; }
359    void setAllowsMemory() { Flags |= CI_AllowsMemory; }
360    void setAllowsRegister() { Flags |= CI_AllowsRegister; }
361    void setHasMatchingInput() { Flags |= CI_HasMatchingInput; }
362
363    /// setTiedOperand - Indicate that this is an input operand that is tied to
364    /// the specified output operand.  Copy over the various constraint
365    /// information from the output.
366    void setTiedOperand(unsigned N, ConstraintInfo &Output) {
367      Output.setHasMatchingInput();
368      Flags = Output.Flags;
369      TiedOperand = N;
370      // Don't copy Name or constraint string.
371    }
372  };
373
374  // validateOutputConstraint, validateInputConstraint - Checks that
375  // a constraint is valid and provides information about it.
376  // FIXME: These should return a real error instead of just true/false.
377  bool validateOutputConstraint(ConstraintInfo &Info) const;
378  bool validateInputConstraint(ConstraintInfo *OutputConstraints,
379                               unsigned NumOutputs,
380                               ConstraintInfo &info) const;
381  bool resolveSymbolicName(const char *&Name,
382                           ConstraintInfo *OutputConstraints,
383                           unsigned NumOutputs, unsigned &Index) const;
384
385  // Constraint parm will be left pointing at the last character of
386  // the constraint.  In practice, it won't be changed unless the
387  // constraint is longer than one character.
388  virtual std::string convertConstraint(const char *&Constraint) const {
389    // 'p' defaults to 'r', but can be overridden by targets.
390    if (*Constraint == 'p')
391      return std::string("r");
392    return std::string(1, *Constraint);
393  }
394
395  // Returns a string of target-specific clobbers, in LLVM format.
396  virtual const char *getClobbers() const = 0;
397
398
399  /// getTriple - Return the target triple of the primary target.
400  const llvm::Triple &getTriple() const {
401    return Triple;
402  }
403
404  const char *getTargetDescription() const {
405    return DescriptionString;
406  }
407
408  struct GCCRegAlias {
409    const char * const Aliases[5];
410    const char * const Register;
411  };
412
413  struct AddlRegName {
414    const char * const Names[5];
415    const unsigned RegNum;
416  };
417
418  virtual bool useGlobalsForAutomaticVariables() const { return false; }
419
420  /// getCFStringSection - Return the section to use for CFString
421  /// literals, or 0 if no special section is used.
422  virtual const char *getCFStringSection() const {
423    return "__DATA,__cfstring";
424  }
425
426  /// getNSStringSection - Return the section to use for NSString
427  /// literals, or 0 if no special section is used.
428  virtual const char *getNSStringSection() const {
429    return "__OBJC,__cstring_object,regular,no_dead_strip";
430  }
431
432  /// getNSStringNonFragileABISection - Return the section to use for
433  /// NSString literals, or 0 if no special section is used (NonFragile ABI).
434  virtual const char *getNSStringNonFragileABISection() const {
435    return "__DATA, __objc_stringobj, regular, no_dead_strip";
436  }
437
438  /// isValidSectionSpecifier - This is an optional hook that targets can
439  /// implement to perform semantic checking on attribute((section("foo")))
440  /// specifiers.  In this case, "foo" is passed in to be checked.  If the
441  /// section specifier is invalid, the backend should return a non-empty string
442  /// that indicates the problem.
443  ///
444  /// This hook is a simple quality of implementation feature to catch errors
445  /// and give good diagnostics in cases when the assembler or code generator
446  /// would otherwise reject the section specifier.
447  ///
448  virtual std::string isValidSectionSpecifier(StringRef SR) const {
449    return "";
450  }
451
452  /// setForcedLangOptions - Set forced language options.
453  /// Apply changes to the target information with respect to certain
454  /// language options which change the target configuration.
455  virtual void setForcedLangOptions(LangOptions &Opts);
456
457  /// getDefaultFeatures - Get the default set of target features for
458  /// the \args CPU; this should include all legal feature strings on
459  /// the target.
460  virtual void getDefaultFeatures(const std::string &CPU,
461                                  llvm::StringMap<bool> &Features) const {
462  }
463
464  /// getABI - Get the ABI in use.
465  virtual const char *getABI() const {
466    return "";
467  }
468
469  /// getCXXABI - Get the C++ ABI in use.
470  virtual TargetCXXABI getCXXABI() const {
471    return CXXABI;
472  }
473
474  /// setCPU - Target the specific CPU.
475  ///
476  /// \return - False on error (invalid CPU name).
477  //
478  // FIXME: Remove this.
479  virtual bool setCPU(const std::string &Name) {
480    return true;
481  }
482
483  /// setABI - Use the specific ABI.
484  ///
485  /// \return - False on error (invalid ABI name).
486  virtual bool setABI(const std::string &Name) {
487    return false;
488  }
489
490  /// setCXXABI - Use this specific C++ ABI.
491  ///
492  /// \return - False on error (invalid C++ ABI name).
493  bool setCXXABI(const std::string &Name) {
494    static const TargetCXXABI Unknown = static_cast<TargetCXXABI>(-1);
495    TargetCXXABI ABI = llvm::StringSwitch<TargetCXXABI>(Name)
496      .Case("arm", CXXABI_ARM)
497      .Case("itanium", CXXABI_Itanium)
498      .Case("microsoft", CXXABI_Microsoft)
499      .Default(Unknown);
500    if (ABI == Unknown) return false;
501    return setCXXABI(ABI);
502  }
503
504  /// setCXXABI - Set the C++ ABI to be used by this implementation.
505  ///
506  /// \return - False on error (ABI not valid on this target)
507  virtual bool setCXXABI(TargetCXXABI ABI) {
508    CXXABI = ABI;
509    return true;
510  }
511
512  /// setFeatureEnabled - Enable or disable a specific target feature,
513  /// the feature name must be valid.
514  ///
515  /// \return - False on error (invalid feature name).
516  virtual bool setFeatureEnabled(llvm::StringMap<bool> &Features,
517                                 const std::string &Name,
518                                 bool Enabled) const {
519    return false;
520  }
521
522  /// HandleTargetOptions - Perform initialization based on the user configured
523  /// set of features (e.g., +sse4). The list is guaranteed to have at most one
524  /// entry per feature.
525  ///
526  /// The target may modify the features list, to change which options are
527  /// passed onwards to the backend.
528  virtual void HandleTargetFeatures(std::vector<std::string> &Features) {
529  }
530
531  // getRegParmMax - Returns maximal number of args passed in registers.
532  unsigned getRegParmMax() const {
533    assert(RegParmMax < 7 && "RegParmMax value is larger than AST can handle");
534    return RegParmMax;
535  }
536
537  /// isTLSSupported - Whether the target supports thread-local storage.
538  bool isTLSSupported() const {
539    return TLSSupported;
540  }
541
542  /// hasNoAsmVariants - Return true if {|} are normal characters in the
543  /// asm string.  If this returns false (the default), then {abc|xyz} is syntax
544  /// that says that when compiling for asm variant #0, "abc" should be
545  /// generated, but when compiling for asm variant #1, "xyz" should be
546  /// generated.
547  bool hasNoAsmVariants() const {
548    return NoAsmVariants;
549  }
550
551  /// getEHDataRegisterNumber - Return the register number that
552  /// __builtin_eh_return_regno would return with the specified argument.
553  virtual int getEHDataRegisterNumber(unsigned RegNo) const {
554    return -1;
555  }
556
557  /// getStaticInitSectionSpecifier - Return the section to use for C++ static
558  /// initialization functions.
559  virtual const char *getStaticInitSectionSpecifier() const {
560    return 0;
561  }
562
563  const LangAS::Map &getAddressSpaceMap() const {
564    return *AddrSpaceMap;
565  }
566
567  /// \brief Retrieve the name of the platform as it is used in the
568  /// availability attribute.
569  StringRef getPlatformName() const { return PlatformName; }
570
571  /// \brief Retrieve the minimum desired version of the platform, to
572  /// which the program should be compiled.
573  VersionTuple getPlatformMinVersion() const { return PlatformMinVersion; }
574
575protected:
576  virtual uint64_t getPointerWidthV(unsigned AddrSpace) const {
577    return PointerWidth;
578  }
579  virtual uint64_t getPointerAlignV(unsigned AddrSpace) const {
580    return PointerAlign;
581  }
582  virtual enum IntType getPtrDiffTypeV(unsigned AddrSpace) const {
583    return PtrDiffType;
584  }
585  virtual void getGCCRegNames(const char * const *&Names,
586                              unsigned &NumNames) const = 0;
587  virtual void getGCCRegAliases(const GCCRegAlias *&Aliases,
588                                unsigned &NumAliases) const = 0;
589  virtual void getGCCAddlRegNames(const AddlRegName *&Addl,
590				  unsigned &NumAddl) const {
591    Addl = 0;
592    NumAddl = 0;
593  }
594  virtual bool validateAsmConstraint(const char *&Name,
595                                     TargetInfo::ConstraintInfo &info) const= 0;
596};
597
598}  // end namespace clang
599
600#endif
601