1 //=====-- PPCSubtarget.h - Define Subtarget for the PPC -------*- 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 declares the PowerPC specific subclass of TargetSubtarget.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef POWERPCSUBTARGET_H
15 #define POWERPCSUBTARGET_H
16 
17 #include "llvm/Target/TargetInstrItineraries.h"
18 #include "llvm/Target/TargetSubtarget.h"
19 
20 #include <string>
21 
22 // GCC #defines PPC on Linux but we use it as our namespace name
23 #undef PPC
24 
25 namespace llvm {
26 
27 namespace PPC {
28   // -m directive values.
29   enum {
30     DIR_NONE,
31     DIR_32,
32     DIR_601,
33     DIR_602,
34     DIR_603,
35     DIR_7400,
36     DIR_750,
37     DIR_970,
38     DIR_64
39   };
40 }
41 
42 class GlobalValue;
43 class TargetMachine;
44 
45 class PPCSubtarget : public TargetSubtarget {
46 protected:
47   /// stackAlignment - The minimum alignment known to hold of the stack frame on
48   /// entry to the function and which must be maintained by every function.
49   unsigned StackAlignment;
50 
51   /// Selected instruction itineraries (one entry per itinerary class.)
52   InstrItineraryData InstrItins;
53 
54   /// Which cpu directive was used.
55   unsigned DarwinDirective;
56 
57   /// Used by the ISel to turn in optimizations for POWER4-derived architectures
58   bool IsGigaProcessor;
59   bool Has64BitSupport;
60   bool Use64BitRegs;
61   bool IsPPC64;
62   bool HasAltivec;
63   bool HasFSQRT;
64   bool HasSTFIWX;
65   bool HasLazyResolverStubs;
66   bool IsJITCodeModel;
67 
68   /// DarwinVers - Nonzero if this is a darwin platform.  Otherwise, the numeric
69   /// version of the platform, e.g. 8 = 10.4 (Tiger), 9 = 10.5 (Leopard), etc.
70   unsigned char DarwinVers; // Is any darwin-ppc platform.
71 public:
72   /// This constructor initializes the data members to match that
73   /// of the specified triple.
74   ///
75   PPCSubtarget(const std::string &TT, const std::string &FS, bool is64Bit);
76 
77   /// ParseSubtargetFeatures - Parses features string setting specified
78   /// subtarget options.  Definition of function is auto generated by tblgen.
79   std::string ParseSubtargetFeatures(const std::string &FS,
80                                      const std::string &CPU);
81 
82 
83   /// SetJITMode - This is called to inform the subtarget info that we are
84   /// producing code for the JIT.
85   void SetJITMode();
86 
87   /// getStackAlignment - Returns the minimum alignment known to hold of the
88   /// stack frame on entry to the function and which must be maintained by every
89   /// function for this subtarget.
getStackAlignment()90   unsigned getStackAlignment() const { return StackAlignment; }
91 
92   /// getDarwinDirective - Returns the -m directive specified for the cpu.
93   ///
getDarwinDirective()94   unsigned getDarwinDirective() const { return DarwinDirective; }
95 
96   /// getInstrItins - Return the instruction itineraies based on subtarget
97   /// selection.
getInstrItineraryData()98   const InstrItineraryData &getInstrItineraryData() const { return InstrItins; }
99 
100   /// getTargetDataString - Return the pointer size and type alignment
101   /// properties of this subtarget.
getTargetDataString()102   const char *getTargetDataString() const {
103     // Note, the alignment values for f64 and i64 on ppc64 in Darwin
104     // documentation are wrong; these are correct (i.e. "what gcc does").
105     return isPPC64() ? "E-p:64:64-f64:64:64-i64:64:64-f128:64:128-n32:64"
106                      : "E-p:32:32-f64:32:64-i64:32:64-f128:64:128-n32";
107   }
108 
109   /// isPPC64 - Return true if we are generating code for 64-bit pointer mode.
110   ///
isPPC64()111   bool isPPC64() const { return IsPPC64; }
112 
113   /// has64BitSupport - Return true if the selected CPU supports 64-bit
114   /// instructions, regardless of whether we are in 32-bit or 64-bit mode.
has64BitSupport()115   bool has64BitSupport() const { return Has64BitSupport; }
116 
117   /// use64BitRegs - Return true if in 64-bit mode or if we should use 64-bit
118   /// registers in 32-bit mode when possible.  This can only true if
119   /// has64BitSupport() returns true.
use64BitRegs()120   bool use64BitRegs() const { return Use64BitRegs; }
121 
122   /// hasLazyResolverStub - Return true if accesses to the specified global have
123   /// to go through a dyld lazy resolution stub.  This means that an extra load
124   /// is required to get the address of the global.
125   bool hasLazyResolverStub(const GlobalValue *GV,
126                            const TargetMachine &TM) const;
127 
128   // isJITCodeModel - True if we're generating code for the JIT
isJITCodeModel()129   bool isJITCodeModel() const { return IsJITCodeModel; }
130 
131   // Specific obvious features.
hasFSQRT()132   bool hasFSQRT() const { return HasFSQRT; }
hasSTFIWX()133   bool hasSTFIWX() const { return HasSTFIWX; }
hasAltivec()134   bool hasAltivec() const { return HasAltivec; }
isGigaProcessor()135   bool isGigaProcessor() const { return IsGigaProcessor; }
136 
137   /// isDarwin - True if this is any darwin platform.
isDarwin()138   bool isDarwin() const { return DarwinVers != 0; }
139   /// isDarwin - True if this is darwin9 (leopard, 10.5) or above.
isDarwin9()140   bool isDarwin9() const { return DarwinVers >= 9; }
141 
142   /// getDarwinVers - Return the darwin version number, 8 = tiger, 9 = leopard.
getDarwinVers()143   unsigned getDarwinVers() const { return DarwinVers; }
144 
isDarwinABI()145   bool isDarwinABI() const { return isDarwin(); }
isSVR4ABI()146   bool isSVR4ABI() const { return !isDarwin(); }
147 
148 };
149 } // End llvm namespace
150 
151 #endif
152