lib/Target/ARM/ARMSubtarget.h

   1 //=====---- ARMSubtarget.h - Define Subtarget for the ARM -----*- 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 ARM specific subclass of TargetSubtarget.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef ARMSUBTARGET_H
  15 #define ARMSUBTARGET_H
  16
  17 #include "llvm/Target/TargetSubtarget.h"
  18 #include <string>
  19
  20 namespace llvm {
  21 class Module;
  22
  23 class ARMSubtarget : public TargetSubtarget {
  24 protected:
  25   enum ARMArchEnum {
  26     V4T, V5T, V5TE, V6
  27   };
  28
  29   /// ARMArchVersion - ARM architecture vecrsion: V4T (base), V5T, V5TE,
  30   /// and V6.
  31   ARMArchEnum ARMArchVersion;
  32
  33   /// HasVFP2 - True if the processor supports Vector Floating Point (VFP) V2
  34   /// instructions.
  35   bool HasVFP2;
  36
  37   /// IsThumb - True if we are in thumb mode, false if in ARM mode.
  38   bool IsThumb;
  39
  40   /// UseThumbBacktraces - True if we use thumb style backtraces.
  41   bool UseThumbBacktraces;
  42
  43   /// IsR9Reserved - True if R9 is a not available as general purpose register.
  44   bool IsR9Reserved;
  45
  46   /// stackAlignment - The minimum alignment known to hold of the stack frame on
  47   /// entry to the function and which must be maintained by every function.
  48   unsigned stackAlignment;
  49
  50  public:
  51   enum {
  52     isELF, isDarwin
  53   } TargetType;
  54
  55   enum {
  56     ARM_ABI_APCS,
  57     ARM_ABI_AAPCS // ARM EABI
  58   } TargetABI;
  59
  60   /// This constructor initializes the data members to match that
  61   /// of the specified module.
  62   ///
  63   ARMSubtarget(const Module &M, const std::string &FS, bool thumb);
  64
  65   /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
  66   /// that still makes it profitable to inline the call.
  67   unsigned getMaxInlineSizeThreshold() const {
  68     // FIXME: For now, we don't lower memcpy's to loads / stores for Thumb.
  69     // Change this once Thumb ldmia / stmia support is added.
  70     return isThumb() ? 0 : 64;
  71   }
  72   /// ParseSubtargetFeatures - Parses features string setting specified
  73   /// subtarget options.  Definition of function is auto generated by tblgen.
  74   void ParseSubtargetFeatures(const std::string &FS, const std::string &CPU);
  75
  76   bool hasV4TOps()  const { return ARMArchVersion >= V4T; }
  77   bool hasV5TOps()  const { return ARMArchVersion >= V5T; }
  78   bool hasV5TEOps() const { return ARMArchVersion >= V5TE; }
  79   bool hasV6Ops()   const { return ARMArchVersion >= V6; }
  80
  81   bool hasVFP2() const { return HasVFP2; }
  82
  83   bool isTargetDarwin() const { return TargetType == isDarwin; }
  84   bool isTargetELF() const { return TargetType == isELF; }
  85
  86   bool isAPCS_ABI() const { return TargetABI == ARM_ABI_APCS; }
  87   bool isAAPCS_ABI() const { return TargetABI == ARM_ABI_AAPCS; }
  88
  89   bool isThumb() const { return IsThumb; }
  90
  91   bool useThumbBacktraces() const { return UseThumbBacktraces; }
  92   bool isR9Reserved() const { return IsR9Reserved; }
  93
  94   /// getStackAlignment - Returns the minimum alignment known to hold of the
  95   /// stack frame on entry to the function and which must be maintained by every
  96   /// function for this subtarget.
  97   unsigned getStackAlignment() const { return stackAlignment; }
  98 };
  99 } // End llvm namespace
 100
 101 #endif  // ARMSUBTARGET_H