lib/Target/ARM/ARMTargetAsmInfo.cpp

   1 //===-- ARMTargetAsmInfo.cpp - ARM asm properties ---------------*- 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 contains the declarations of the ARMTargetAsmInfo properties.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "ARMTargetAsmInfo.h"
  15 #include "ARMTargetMachine.h"
  16 #include <cstring>
  17 #include <cctype>
  18 using namespace llvm;
  19
  20 static const char *const arm_asm_table[] = {
  21                                       "{r0}", "r0",
  22                                       "{r1}", "r1",
  23                                       "{r2}", "r2",
  24                                       "{r3}", "r3",
  25                                       "{r4}", "r4",
  26                                       "{r5}", "r5",
  27                                       "{r6}", "r6",
  28                                       "{r7}", "r7",
  29                                       "{r8}", "r8",
  30                                       "{r9}", "r9",
  31                                       "{r10}", "r10",
  32                                       "{r11}", "r11",
  33                                       "{r12}", "r12",
  34                                       "{r13}", "r13",
  35                                       "{r14}", "r14",
  36                                       "{lr}", "lr",
  37                                       "{sp}", "sp",
  38                                       "{ip}", "ip",
  39                                       "{fp}", "fp",
  40                                       "{sl}", "sl",
  41                                       "{memory}", "memory",
  42                                       "{cc}", "cc",
  43                                       0,0};
  44
  45 ARMTargetAsmInfo::ARMTargetAsmInfo(const ARMTargetMachine &TM) {
  46   AsmTransCBE = arm_asm_table;
  47
  48   AlignmentIsInBytes = false;
  49   Data64bitsDirective = 0;
  50   CommentString = "@";
  51   ConstantPoolSection = "\t.text\n";
  52   COMMDirectiveTakesAlignment = false;
  53   InlineAsmStart = "@ InlineAsm Start";
  54   InlineAsmEnd = "@ InlineAsm End";
  55   LCOMMDirective = "\t.lcomm\t";
  56 }
  57
  58 ARMDarwinTargetAsmInfo::ARMDarwinTargetAsmInfo(const ARMTargetMachine &TM):
  59   ARMTargetAsmInfo(TM), DarwinTargetAsmInfo(TM) {
  60   Subtarget = &DTM->getSubtarget<ARMSubtarget>();
  61
  62   GlobalPrefix = "_";
  63   PrivateGlobalPrefix = "L";
  64   LessPrivateGlobalPrefix = "l";
  65   StringConstantPrefix = "\1LC";
  66   BSSSection = 0;                       // no BSS section
  67   ZeroDirective = "\t.space\t";
  68   ZeroFillDirective = "\t.zerofill\t";  // Uses .zerofill
  69   SetDirective = "\t.set\t";
  70   WeakRefDirective = "\t.weak_reference\t";
  71   HiddenDirective = "\t.private_extern\t";
  72   ProtectedDirective = NULL;
  73   JumpTableDataSection = ".const";
  74   CStringSection = "\t.cstring";
  75   ReadOnlySection = "\t.const\n";
  76   HasDotTypeDotSizeDirective = false;
  77   NeedsIndirectEncoding = true;
  78   if (TM.getRelocationModel() == Reloc::Static) {
  79     StaticCtorsSection = ".constructor";
  80     StaticDtorsSection = ".destructor";
  81   } else {
  82     StaticCtorsSection = ".mod_init_func";
  83     StaticDtorsSection = ".mod_term_func";
  84   }
  85
  86   // In non-PIC modes, emit a special label before jump tables so that the
  87   // linker can perform more accurate dead code stripping.
  88   if (TM.getRelocationModel() != Reloc::PIC_) {
  89     // Emit a local label that is preserved until the linker runs.
  90     JumpTableSpecialLabelPrefix = "l";
  91   }
  92
  93   NeedsSet = true;
  94   DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
  95   DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
  96   DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
  97   DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
  98   DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
  99   DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
 100   DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
 101   DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
 102   DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
 103   DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
 104   DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
 105 }
 106
 107 ARMELFTargetAsmInfo::ARMELFTargetAsmInfo(const ARMTargetMachine &TM):
 108   ARMTargetAsmInfo(TM), ELFTargetAsmInfo(TM) {
 109   Subtarget = &ETM->getSubtarget<ARMSubtarget>();
 110
 111   NeedsSet = false;
 112   HasLEB128 = true;
 113   AbsoluteDebugSectionOffsets = true;
 114   CStringSection = ".rodata.str";
 115   ReadOnlySection = "\t.section\t.rodata\n";
 116   PrivateGlobalPrefix = ".L";
 117   WeakRefDirective = "\t.weak\t";
 118   SetDirective = "\t.set\t";
 119   DwarfRequiresFrameSection = false;
 120   DwarfAbbrevSection =  "\t.section\t.debug_abbrev,\"\",%progbits";
 121   DwarfInfoSection =    "\t.section\t.debug_info,\"\",%progbits";
 122   DwarfLineSection =    "\t.section\t.debug_line,\"\",%progbits";
 123   DwarfFrameSection =   "\t.section\t.debug_frame,\"\",%progbits";
 124   DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",%progbits";
 125   DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",%progbits";
 126   DwarfStrSection =     "\t.section\t.debug_str,\"\",%progbits";
 127   DwarfLocSection =     "\t.section\t.debug_loc,\"\",%progbits";
 128   DwarfARangesSection = "\t.section\t.debug_aranges,\"\",%progbits";
 129   DwarfRangesSection =  "\t.section\t.debug_ranges,\"\",%progbits";
 130   DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",%progbits";
 131
 132   if (Subtarget->isAAPCS_ABI()) {
 133     StaticCtorsSection = "\t.section .init_array,\"aw\",%init_array";
 134     StaticDtorsSection = "\t.section .fini_array,\"aw\",%fini_array";
 135   } else {
 136     StaticCtorsSection = "\t.section .ctors,\"aw\",%progbits";
 137     StaticDtorsSection = "\t.section .dtors,\"aw\",%progbits";
 138   }
 139 }
 140
 141 /// Count the number of comma-separated arguments.
 142 /// Do not try to detect errors.
 143 unsigned ARMTargetAsmInfo::countArguments(const char* p) const {
 144   unsigned count = 0;
 145   while (*p && isspace(*p) && *p != '\n')
 146     p++;
 147   count++;
 148   while (*p && *p!='\n' &&
 149          strncmp(p, CommentString, strlen(CommentString))!=0) {
 150     if (*p==',')
 151       count++;
 152     p++;
 153   }
 154   return count;
 155 }
 156
 157 /// Count the length of a string enclosed in quote characters.
 158 /// Do not try to detect errors.
 159 unsigned ARMTargetAsmInfo::countString(const char* p) const {
 160   unsigned count = 0;
 161   while (*p && isspace(*p) && *p!='\n')
 162     p++;
 163   if (!*p || *p != '\"')
 164     return count;
 165   while (*++p && *p != '\"')
 166     count++;
 167   return count;
 168 }
 169
 170 /// ARM-specific version of TargetAsmInfo::getInlineAsmLength.
 171 unsigned ARMTargetAsmInfo::getInlineAsmLength(const char *s) const {
 172   // Make a lowercase-folded version of s for counting purposes.
 173   char *q, *s_copy = (char *)malloc(strlen(s) + 1);
 174   strcpy(s_copy, s);
 175   for (q=s_copy; *q; q++)
 176     *q = tolower(*q);
 177   const char *Str = s_copy;
 178
 179   // Count the number of bytes in the asm.
 180   bool atInsnStart = true;
 181   bool inTextSection = true;
 182   unsigned Length = 0;
 183   for (; *Str; ++Str) {
 184     if (atInsnStart) {
 185       // Skip whitespace
 186       while (*Str && isspace(*Str) && *Str != '\n')
 187         Str++;
 188       // Skip label
 189       for (const char* p = Str; *p && !isspace(*p); p++)
 190         if (*p == ':') {
 191           Str = p+1;
 192           while (*Str && isspace(*Str) && *Str != '\n')
 193             Str++;
 194           break;
 195         }
 196       // Ignore everything from comment char(s) to EOL
 197       if (strncmp(Str, CommentString, strlen(CommentString))==-0)
 198         atInsnStart = false;
 199       // FIXME do something like the following for non-Darwin
 200       else if (*Str == '.' && Subtarget->isTargetDarwin()) {
 201         // Directive.
 202         atInsnStart = false;
 203
 204         // Some change the section, but don't generate code.
 205         if (strncmp(Str, ".literal4", strlen(".literal4"))==0 ||
 206             strncmp(Str, ".literal8", strlen(".literal8"))==0 ||
 207             strncmp(Str, ".const", strlen(".const"))==0 ||
 208             strncmp(Str, ".constructor", strlen(".constructor"))==0 ||
 209             strncmp(Str, ".cstring", strlen(".cstring"))==0 ||
 210             strncmp(Str, ".data", strlen(".data"))==0 ||
 211             strncmp(Str, ".destructor", strlen(".destructor"))==0 ||
 212             strncmp(Str, ".fvmlib_init0", strlen(".fvmlib_init0"))==0 ||
 213             strncmp(Str, ".fvmlib_init1", strlen(".fvmlib_init1"))==0 ||
 214             strncmp(Str, ".mod_init_func", strlen(".mod_init_func"))==0 ||
 215             strncmp(Str, ".mod_term_func", strlen(".mod_term_func"))==0 ||
 216             strncmp(Str, ".picsymbol_stub", strlen(".picsymbol_stub"))==0 ||
 217             strncmp(Str, ".symbol_stub", strlen(".symbol_stub"))==0 ||
 218             strncmp(Str, ".static_data", strlen(".static_data"))==0 ||
 219             strncmp(Str, ".section", strlen(".section"))==0 ||
 220             strncmp(Str, ".lazy_symbol_pointer", strlen(".lazy_symbol_pointer"))==0 ||
 221             strncmp(Str, ".non_lazy_symbol_pointer", strlen(".non_lazy_symbol_pointer"))==0 ||
 222             strncmp(Str, ".dyld", strlen(".dyld"))==0 ||
 223             strncmp(Str, ".const_data", strlen(".const_data"))==0 ||
 224             strncmp(Str, ".objc", strlen(".objc"))==0 ||       //// many directives
 225             strncmp(Str, ".static_const", strlen(".static_const"))==0)
 226           inTextSection=false;
 227         else if (strncmp(Str, ".text", strlen(".text"))==0)
 228           inTextSection = true;
 229         // Some can't really be handled without implementing significant pieces
 230         // of an assembler.  Others require dynamic adjustment of block sizes in
 231         // AdjustBBOffsetsAfter; it's a big compile-time speed hit to check every
 232         // instruction in there, and none of these are currently used in the kernel.
 233         else if (strncmp(Str, ".macro", strlen(".macro"))==0 ||
 234                  strncmp(Str, ".if", strlen(".if"))==0 ||
 235                  strncmp(Str, ".align", strlen(".align"))==0 ||
 236                  strncmp(Str, ".fill", strlen(".fill"))==0 ||
 237                  strncmp(Str, ".space", strlen(".space"))==0 ||
 238                  strncmp(Str, ".zerofill", strlen(".zerofill"))==0 ||
 239                  strncmp(Str, ".p2align", strlen(".p2align"))==0 ||
 240                  strncmp(Str, ".p2alignw", strlen(".p2alignw"))==0 ||
 241                  strncmp(Str, ".p2alignl", strlen(".p2alignl"))==0 ||
 242                  strncmp(Str, ".align32", strlen(".p2align32"))==0 ||
 243                  strncmp(Str, ".include", strlen(".include"))==0)
 244           cerr << "Directive " << Str << " in asm may lead to invalid offsets for" <<
 245                    " constant pools (the assembler will tell you if this happens).\n";
 246         // Some generate code, but this is only interesting in the text section.
 247         else if (inTextSection) {
 248           if (strncmp(Str, ".long", strlen(".long"))==0)
 249             Length += 4*countArguments(Str+strlen(".long"));
 250           else if (strncmp(Str, ".short", strlen(".short"))==0)
 251             Length += 2*countArguments(Str+strlen(".short"));
 252           else if (strncmp(Str, ".byte", strlen(".byte"))==0)
 253             Length += 1*countArguments(Str+strlen(".byte"));
 254           else if (strncmp(Str, ".single", strlen(".single"))==0)
 255             Length += 4*countArguments(Str+strlen(".single"));
 256           else if (strncmp(Str, ".double", strlen(".double"))==0)
 257             Length += 8*countArguments(Str+strlen(".double"));
 258           else if (strncmp(Str, ".quad", strlen(".quad"))==0)
 259             Length += 16*countArguments(Str+strlen(".quad"));
 260           else if (strncmp(Str, ".ascii", strlen(".ascii"))==0)
 261             Length += countString(Str+strlen(".ascii"));
 262           else if (strncmp(Str, ".asciz", strlen(".asciz"))==0)
 263             Length += countString(Str+strlen(".asciz"))+1;
 264         }
 265       } else if (inTextSection) {
 266         // An instruction
 267         atInsnStart = false;
 268         if (Subtarget->isThumb()) {
 269           // BL and BLX <non-reg> are 4 bytes, all others 2.
 270           if (strncmp(Str, "blx", strlen("blx"))==0) {
 271             const char* p = Str+3;
 272             while (*p && isspace(*p))
 273               p++;
 274             if (*p == 'r' || *p=='R')
 275               Length += 2;    // BLX reg
 276             else
 277               Length += 4;    // BLX non-reg
 278           } else if (strncmp(Str, "bl", strlen("bl"))==0)
 279             Length += 4;    // BL
 280           else
 281             Length += 2;    // Thumb anything else
 282         }
 283         else
 284           Length += 4;    // ARM
 285       }
 286     }
 287     if (*Str == '\n' || *Str == SeparatorChar)
 288       atInsnStart = true;
 289   }
 290   free(s_copy);
 291   return Length;
 292 }