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   DataSection = "\t.data";
  52   ConstantPoolSection = "\t.text\n";
  53   COMMDirectiveTakesAlignment = false;
  54   InlineAsmStart = "@ InlineAsm Start";
  55   InlineAsmEnd = "@ InlineAsm End";
  56   LCOMMDirective = "\t.lcomm\t";
  57 }
  58
  59 ARMDarwinTargetAsmInfo::ARMDarwinTargetAsmInfo(const ARMTargetMachine &TM):
  60   ARMTargetAsmInfo(TM), DarwinTargetAsmInfo(TM) {
  61   Subtarget = &DTM->getSubtarget<ARMSubtarget>();
  62
  63   GlobalPrefix = "_";
  64   PrivateGlobalPrefix = "L";
  65   LessPrivateGlobalPrefix = "l";
  66   StringConstantPrefix = "\1LC";
  67   BSSSection = 0;                       // no BSS section
  68   ZeroDirective = "\t.space\t";
  69   ZeroFillDirective = "\t.zerofill\t";  // Uses .zerofill
  70   SetDirective = "\t.set\t";
  71   WeakRefDirective = "\t.weak_reference\t";
  72   HiddenDirective = "\t.private_extern\t";
  73   ProtectedDirective = NULL;
  74   JumpTableDataSection = ".const";
  75   CStringSection = "\t.cstring";
  76   FourByteConstantSection = "\t.literal4\n";
  77   EightByteConstantSection = "\t.literal8\n";
  78   ReadOnlySection = "\t.const\n";
  79   HasDotTypeDotSizeDirective = false;
  80   NeedsIndirectEncoding = true;
  81   if (TM.getRelocationModel() == Reloc::Static) {
  82     StaticCtorsSection = ".constructor";
  83     StaticDtorsSection = ".destructor";
  84   } else {
  85     StaticCtorsSection = ".mod_init_func";
  86     StaticDtorsSection = ".mod_term_func";
  87   }
  88
  89   // In non-PIC modes, emit a special label before jump tables so that the
  90   // linker can perform more accurate dead code stripping.
  91   if (TM.getRelocationModel() != Reloc::PIC_) {
  92     // Emit a local label that is preserved until the linker runs.
  93     JumpTableSpecialLabelPrefix = "l";
  94   }
  95
  96   NeedsSet = true;
  97   DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
  98   DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
  99   DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
 100   DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
 101   DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
 102   DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
 103   DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
 104   DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
 105   DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
 106   DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
 107   DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
 108 }
 109
 110 ARMELFTargetAsmInfo::ARMELFTargetAsmInfo(const ARMTargetMachine &TM):
 111   ARMTargetAsmInfo(TM), ELFTargetAsmInfo(TM) {
 112   Subtarget = &ETM->getSubtarget<ARMSubtarget>();
 113
 114   NeedsSet = false;
 115   HasLEB128 = true;
 116   AbsoluteDebugSectionOffsets = true;
 117   CStringSection = ".rodata.str";
 118   ReadOnlySection = "\t.section\t.rodata\n";
 119   FourByteConstantSection = "\t.section\t.rodata.cst4,\"aM\",@progbits,4";
 120   EightByteConstantSection = "\t.section\t.rodata.cst8,\"aM\",@progbits,8";
 121   SixteenByteConstantSection = "\t.section\t.rodata.cst16,\"aM\",@progbits,16";
 122   PrivateGlobalPrefix = ".L";
 123   WeakRefDirective = "\t.weak\t";
 124   SetDirective = "\t.set\t";
 125   DwarfRequiresFrameSection = false;
 126   DwarfAbbrevSection =  "\t.section\t.debug_abbrev,\"\",%progbits";
 127   DwarfInfoSection =    "\t.section\t.debug_info,\"\",%progbits";
 128   DwarfLineSection =    "\t.section\t.debug_line,\"\",%progbits";
 129   DwarfFrameSection =   "\t.section\t.debug_frame,\"\",%progbits";
 130   DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",%progbits";
 131   DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",%progbits";
 132   DwarfStrSection =     "\t.section\t.debug_str,\"\",%progbits";
 133   DwarfLocSection =     "\t.section\t.debug_loc,\"\",%progbits";
 134   DwarfARangesSection = "\t.section\t.debug_aranges,\"\",%progbits";
 135   DwarfRangesSection =  "\t.section\t.debug_ranges,\"\",%progbits";
 136   DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",%progbits";
 137
 138   if (Subtarget->isAAPCS_ABI()) {
 139     StaticCtorsSection = "\t.section .init_array,\"aw\",%init_array";
 140     StaticDtorsSection = "\t.section .fini_array,\"aw\",%fini_array";
 141   } else {
 142     StaticCtorsSection = "\t.section .ctors,\"aw\",%progbits";
 143     StaticDtorsSection = "\t.section .dtors,\"aw\",%progbits";
 144   }
 145   TLSDataSection = "\t.section .tdata,\"awT\",%progbits";
 146   TLSBSSSection = "\t.section .tbss,\"awT\",%nobits";
 147 }
 148
 149 /// Count the number of comma-separated arguments.
 150 /// Do not try to detect errors.
 151 unsigned ARMTargetAsmInfo::countArguments(const char* p) const {
 152   unsigned count = 0;
 153   while (*p && isspace(*p) && *p != '\n')
 154     p++;
 155   count++;
 156   while (*p && *p!='\n' &&
 157          strncmp(p, CommentString, strlen(CommentString))!=0) {
 158     if (*p==',')
 159       count++;
 160     p++;
 161   }
 162   return count;
 163 }
 164
 165 /// Count the length of a string enclosed in quote characters.
 166 /// Do not try to detect errors.
 167 unsigned ARMTargetAsmInfo::countString(const char* p) const {
 168   unsigned count = 0;
 169   while (*p && isspace(*p) && *p!='\n')
 170     p++;
 171   if (!*p || *p != '\"')
 172     return count;
 173   while (*++p && *p != '\"')
 174     count++;
 175   return count;
 176 }
 177
 178 /// ARM-specific version of TargetAsmInfo::getInlineAsmLength.
 179 unsigned ARMTargetAsmInfo::getInlineAsmLength(const char *s) const {
 180   // Make a lowercase-folded version of s for counting purposes.
 181   char *q, *s_copy = (char *)malloc(strlen(s) + 1);
 182   strcpy(s_copy, s);
 183   for (q=s_copy; *q; q++)
 184     *q = tolower(*q);
 185   const char *Str = s_copy;
 186
 187   // Count the number of bytes in the asm.
 188   bool atInsnStart = true;
 189   bool inTextSection = true;
 190   unsigned Length = 0;
 191   for (; *Str; ++Str) {
 192     if (atInsnStart) {
 193       // Skip whitespace
 194       while (*Str && isspace(*Str) && *Str != '\n')
 195         Str++;
 196       // Skip label
 197       for (const char* p = Str; *p && !isspace(*p); p++)
 198         if (*p == ':') {
 199           Str = p+1;
 200           while (*Str && isspace(*Str) && *Str != '\n')
 201             Str++;
 202           break;
 203         }
 204       // Ignore everything from comment char(s) to EOL
 205       if (strncmp(Str, CommentString, strlen(CommentString))==-0)
 206         atInsnStart = false;
 207       // FIXME do something like the following for non-Darwin
 208       else if (*Str == '.' && Subtarget->isTargetDarwin()) {
 209         // Directive.
 210         atInsnStart = false;
 211
 212         // Some change the section, but don't generate code.
 213         if (strncmp(Str, ".literal4", strlen(".literal4"))==0 ||
 214             strncmp(Str, ".literal8", strlen(".literal8"))==0 ||
 215             strncmp(Str, ".const", strlen(".const"))==0 ||
 216             strncmp(Str, ".constructor", strlen(".constructor"))==0 ||
 217             strncmp(Str, ".cstring", strlen(".cstring"))==0 ||
 218             strncmp(Str, ".data", strlen(".data"))==0 ||
 219             strncmp(Str, ".destructor", strlen(".destructor"))==0 ||
 220             strncmp(Str, ".fvmlib_init0", strlen(".fvmlib_init0"))==0 ||
 221             strncmp(Str, ".fvmlib_init1", strlen(".fvmlib_init1"))==0 ||
 222             strncmp(Str, ".mod_init_func", strlen(".mod_init_func"))==0 ||
 223             strncmp(Str, ".mod_term_func", strlen(".mod_term_func"))==0 ||
 224             strncmp(Str, ".picsymbol_stub", strlen(".picsymbol_stub"))==0 ||
 225             strncmp(Str, ".symbol_stub", strlen(".symbol_stub"))==0 ||
 226             strncmp(Str, ".static_data", strlen(".static_data"))==0 ||
 227             strncmp(Str, ".section", strlen(".section"))==0 ||
 228             strncmp(Str, ".lazy_symbol_pointer", strlen(".lazy_symbol_pointer"))==0 ||
 229             strncmp(Str, ".non_lazy_symbol_pointer", strlen(".non_lazy_symbol_pointer"))==0 ||
 230             strncmp(Str, ".dyld", strlen(".dyld"))==0 ||
 231             strncmp(Str, ".const_data", strlen(".const_data"))==0 ||
 232             strncmp(Str, ".objc", strlen(".objc"))==0 ||       //// many directives
 233             strncmp(Str, ".static_const", strlen(".static_const"))==0)
 234           inTextSection=false;
 235         else if (strncmp(Str, ".text", strlen(".text"))==0)
 236           inTextSection = true;
 237         // Some can't really be handled without implementing significant pieces
 238         // of an assembler.  Others require dynamic adjustment of block sizes in
 239         // AdjustBBOffsetsAfter; it's a big compile-time speed hit to check every
 240         // instruction in there, and none of these are currently used in the kernel.
 241         else if (strncmp(Str, ".macro", strlen(".macro"))==0 ||
 242                  strncmp(Str, ".if", strlen(".if"))==0 ||
 243                  strncmp(Str, ".align", strlen(".align"))==0 ||
 244                  strncmp(Str, ".fill", strlen(".fill"))==0 ||
 245                  strncmp(Str, ".space", strlen(".space"))==0 ||
 246                  strncmp(Str, ".zerofill", strlen(".zerofill"))==0 ||
 247                  strncmp(Str, ".p2align", strlen(".p2align"))==0 ||
 248                  strncmp(Str, ".p2alignw", strlen(".p2alignw"))==0 ||
 249                  strncmp(Str, ".p2alignl", strlen(".p2alignl"))==0 ||
 250                  strncmp(Str, ".align32", strlen(".p2align32"))==0 ||
 251                  strncmp(Str, ".include", strlen(".include"))==0)
 252           cerr << "Directive " << Str << " in asm may lead to invalid offsets for" <<
 253                    " constant pools (the assembler will tell you if this happens).\n";
 254         // Some generate code, but this is only interesting in the text section.
 255         else if (inTextSection) {
 256           if (strncmp(Str, ".long", strlen(".long"))==0)
 257             Length += 4*countArguments(Str+strlen(".long"));
 258           else if (strncmp(Str, ".short", strlen(".short"))==0)
 259             Length += 2*countArguments(Str+strlen(".short"));
 260           else if (strncmp(Str, ".byte", strlen(".byte"))==0)
 261             Length += 1*countArguments(Str+strlen(".byte"));
 262           else if (strncmp(Str, ".single", strlen(".single"))==0)
 263             Length += 4*countArguments(Str+strlen(".single"));
 264           else if (strncmp(Str, ".double", strlen(".double"))==0)
 265             Length += 8*countArguments(Str+strlen(".double"));
 266           else if (strncmp(Str, ".quad", strlen(".quad"))==0)
 267             Length += 16*countArguments(Str+strlen(".quad"));
 268           else if (strncmp(Str, ".ascii", strlen(".ascii"))==0)
 269             Length += countString(Str+strlen(".ascii"));
 270           else if (strncmp(Str, ".asciz", strlen(".asciz"))==0)
 271             Length += countString(Str+strlen(".asciz"))+1;
 272         }
 273       } else if (inTextSection) {
 274         // An instruction
 275         atInsnStart = false;
 276         if (Subtarget->isThumb()) {
 277           // BL and BLX <non-reg> are 4 bytes, all others 2.
 278           if (strncmp(Str, "blx", strlen("blx"))==0) {
 279             const char* p = Str+3;
 280             while (*p && isspace(*p))
 281               p++;
 282             if (*p == 'r' || *p=='R')
 283               Length += 2;    // BLX reg
 284             else
 285               Length += 4;    // BLX non-reg
 286           } else if (strncmp(Str, "bl", strlen("bl"))==0)
 287             Length += 4;    // BL
 288           else
 289             Length += 2;    // Thumb anything else
 290         }
 291         else
 292           Length += 4;    // ARM
 293       }
 294     }
 295     if (*Str == '\n' || *Str == SeparatorChar)
 296       atInsnStart = true;
 297   }
 298   free(s_copy);
 299   return Length;
 300 }