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