lib/Target/ARM/ARMTargetAsmInfo.cpp

   1
   2 //===-- ARMTargetAsmInfo.cpp - ARM asm properties ---------------*- C++ -*-===//
   3 //
   4 //                     The LLVM Compiler Infrastructure
   5 //
   6 // This file was developed by James M. Laskey and is distributed under the
   7 // University of Illinois Open Source License. See LICENSE.TXT for details.
   8 //
   9 //===----------------------------------------------------------------------===//
  10 //
  11 // This file contains the declarations of the ARMTargetAsmInfo properties.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "ARMTargetAsmInfo.h"
  16 #include "ARMTargetMachine.h"
  17 #include <cstring>
  18 #include <cctype>
  19 using namespace llvm;
  20
  21 static const char* arm_asm_table[] = {"{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     BSSSection = 0;                       // no BSS section.
  52     ZeroFillDirective = "\t.zerofill\t";  // Uses .zerofill
  53     SetDirective = "\t.set";
  54     WeakRefDirective = "\t.weak_reference\t";
  55     HiddenDirective = "\t.private_extern\t";
  56     ProtectedDirective = NULL;
  57     JumpTableDataSection = ".const";
  58     CStringSection = "\t.cstring";
  59     FourByteConstantSection = "\t.literal4\n";
  60     EightByteConstantSection = "\t.literal8\n";
  61     ReadOnlySection = "\t.const\n";
  62     HasDotTypeDotSizeDirective = false;
  63     NeedsIndirectEncoding = true;
  64     if (TM.getRelocationModel() == Reloc::Static) {
  65       StaticCtorsSection = ".constructor";
  66       StaticDtorsSection = ".destructor";
  67     } else {
  68       StaticCtorsSection = ".mod_init_func";
  69       StaticDtorsSection = ".mod_term_func";
  70     }
  71
  72     // In non-PIC modes, emit a special label before jump tables so that the
  73     // linker can perform more accurate dead code stripping.
  74     if (TM.getRelocationModel() != Reloc::PIC_) {
  75       // Emit a local label that is preserved until the linker runs.
  76       JumpTableSpecialLabelPrefix = "l";
  77     }
  78
  79     NeedsSet = true;
  80     DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
  81     DwarfInfoSection = ".section __DWARF,__debug_info,regular,debug";
  82     DwarfLineSection = ".section __DWARF,__debug_line,regular,debug";
  83     DwarfFrameSection = ".section __DWARF,__debug_frame,regular,debug";
  84     DwarfPubNamesSection = ".section __DWARF,__debug_pubnames,regular,debug";
  85     DwarfPubTypesSection = ".section __DWARF,__debug_pubtypes,regular,debug";
  86     DwarfStrSection = ".section __DWARF,__debug_str,regular,debug";
  87     DwarfLocSection = ".section __DWARF,__debug_loc,regular,debug";
  88     DwarfARangesSection = ".section __DWARF,__debug_aranges,regular,debug";
  89     DwarfRangesSection = ".section __DWARF,__debug_ranges,regular,debug";
  90     DwarfMacInfoSection = ".section __DWARF,__debug_macinfo,regular,debug";
  91   } else {
  92     NeedsSet = false;
  93     HasLEB128 = true;
  94     AbsoluteDebugSectionOffsets = true;
  95     ReadOnlySection = "\t.section\t.rodata\n";
  96     PrivateGlobalPrefix = ".L";
  97     WeakRefDirective = "\t.weak\t";
  98     SetDirective = "\t.set\t";
  99     DwarfRequiresFrameSection = false;
 100     DwarfAbbrevSection =  "\t.section\t.debug_abbrev,\"\",%progbits";
 101     DwarfInfoSection =    "\t.section\t.debug_info,\"\",%progbits";
 102     DwarfLineSection =    "\t.section\t.debug_line,\"\",%progbits";
 103     DwarfFrameSection =   "\t.section\t.debug_frame,\"\",%progbits";
 104     DwarfPubNamesSection ="\t.section\t.debug_pubnames,\"\",%progbits";
 105     DwarfPubTypesSection ="\t.section\t.debug_pubtypes,\"\",%progbits";
 106     DwarfStrSection =     "\t.section\t.debug_str,\"\",%progbits";
 107     DwarfLocSection =     "\t.section\t.debug_loc,\"\",%progbits";
 108     DwarfARangesSection = "\t.section\t.debug_aranges,\"\",%progbits";
 109     DwarfRangesSection =  "\t.section\t.debug_ranges,\"\",%progbits";
 110     DwarfMacInfoSection = "\t.section\t.debug_macinfo,\"\",%progbits";
 111
 112     if (Subtarget->isAAPCS_ABI()) {
 113       StaticCtorsSection = "\t.section .init_array,\"aw\",%init_array";
 114       StaticDtorsSection = "\t.section .fini_array,\"aw\",%fini_array";
 115     } else {
 116       StaticCtorsSection = "\t.section .ctors,\"aw\",%progbits";
 117       StaticDtorsSection = "\t.section .dtors,\"aw\",%progbits";
 118     }
 119     TLSDataSection = "\t.section .tdata,\"awT\",%progbits";
 120     TLSBSSSection = "\t.section .tbss,\"awT\",%nobits";
 121   }
 122
 123   ZeroDirective = "\t.space\t";
 124   AlignmentIsInBytes = false;
 125   Data64bitsDirective = 0;
 126   CommentString = "@";
 127   DataSection = "\t.data";
 128   ConstantPoolSection = "\t.text\n";
 129   COMMDirectiveTakesAlignment = false;
 130   InlineAsmStart = "@ InlineAsm Start";
 131   InlineAsmEnd = "@ InlineAsm End";
 132   LCOMMDirective = "\t.lcomm\t";
 133 }
 134
 135 /// Count the number of comma-separated arguments.
 136 /// Do not try to detect errors.
 137 unsigned ARMTargetAsmInfo::countArguments(const char* p) const {
 138   unsigned count = 0;
 139   while (*p && isspace(*p) && *p != '\n')
 140     p++;
 141   count++;
 142   while (*p && *p!='\n' &&
 143          strncmp(p, CommentString, strlen(CommentString))!=0) {
 144     if (*p==',')
 145       count++;
 146     p++;
 147   }
 148   return count;
 149 }
 150
 151 /// Count the length of a string enclosed in quote characters.
 152 /// Do not try to detect errors.
 153 unsigned ARMTargetAsmInfo::countString(const char* p) const {
 154   unsigned count = 0;
 155   while (*p && isspace(*p) && *p!='\n')
 156     p++;
 157   if (!*p || *p != '\"')
 158     return count;
 159   while (*++p && *p != '\"')
 160     count++;
 161   return count;
 162 }
 163
 164 /// ARM-specific version of TargetAsmInfo::getInlineAsmLength.
 165 unsigned ARMTargetAsmInfo::getInlineAsmLength(const char *s) const {
 166   // Make a lowercase-folded version of s for counting purposes.
 167   char *q, *s_copy = (char *)malloc(strlen(s) + 1);
 168   strcpy(s_copy, s);
 169   for (q=s_copy; *q; q++)
 170     *q = tolower(*q);
 171   const char *Str = s_copy;
 172
 173   // Count the number of bytes in the asm.
 174   bool atInsnStart = true;
 175   bool inTextSection = true;
 176   unsigned Length = 0;
 177   for (; *Str; ++Str) {
 178     if (atInsnStart) {
 179       // Skip whitespace
 180       while (*Str && isspace(*Str) && *Str != '\n')
 181         Str++;
 182       // Skip label
 183       for (const char* p = Str; *p && !isspace(*p); p++)
 184         if (*p == ':') {
 185           Str = p+1;
 186           while (*Str && isspace(*Str) && *Str != '\n')
 187             Str++;
 188           break;
 189         }
 190       // Ignore everything from comment char(s) to EOL
 191       if (strncmp(Str, CommentString, strlen(CommentString))==-0)
 192         atInsnStart = false;
 193       // FIXME do something like the following for non-Darwin
 194       else if (*Str == '.' && Subtarget->isTargetDarwin()) {
 195         // Directive.
 196         atInsnStart = false;
 197
 198         // Some change the section, but don't generate code.
 199         if (strncmp(Str, ".literal4", strlen(".literal4"))==0 ||
 200             strncmp(Str, ".literal8", strlen(".literal8"))==0 ||
 201             strncmp(Str, ".const", strlen(".const"))==0 ||
 202             strncmp(Str, ".constructor", strlen(".constructor"))==0 ||
 203             strncmp(Str, ".cstring", strlen(".cstring"))==0 ||
 204             strncmp(Str, ".data", strlen(".data"))==0 ||
 205             strncmp(Str, ".destructor", strlen(".destructor"))==0 ||
 206             strncmp(Str, ".fvmlib_init0", strlen(".fvmlib_init0"))==0 ||
 207             strncmp(Str, ".fvmlib_init1", strlen(".fvmlib_init1"))==0 ||
 208             strncmp(Str, ".mod_init_func", strlen(".mod_init_func"))==0 ||
 209             strncmp(Str, ".mod_term_func", strlen(".mod_term_func"))==0 ||
 210             strncmp(Str, ".picsymbol_stub", strlen(".picsymbol_stub"))==0 ||
 211             strncmp(Str, ".symbol_stub", strlen(".symbol_stub"))==0 ||
 212             strncmp(Str, ".static_data", strlen(".static_data"))==0 ||
 213             strncmp(Str, ".section", strlen(".section"))==0 ||
 214             strncmp(Str, ".lazy_symbol_pointer", strlen(".lazy_symbol_pointer"))==0 ||
 215             strncmp(Str, ".non_lazy_symbol_pointer", strlen(".non_lazy_symbol_pointer"))==0 ||
 216             strncmp(Str, ".dyld", strlen(".dyld"))==0 ||
 217             strncmp(Str, ".const_data", strlen(".const_data"))==0 ||
 218             strncmp(Str, ".objc", strlen(".objc"))==0 ||       //// many directives
 219             strncmp(Str, ".static_const", strlen(".static_const"))==0)
 220           inTextSection=false;
 221         else if (strncmp(Str, ".text", strlen(".text"))==0)
 222           inTextSection = true;
 223         // Some can't really be handled without implementing significant pieces
 224         // of an assembler.  Others require dynamic adjustment of block sizes in
 225         // AdjustBBOffsetsAfter; it's a big compile-time speed hit to check every
 226         // instruction in there, and none of these are currently used in the kernel.
 227         else if (strncmp(Str, ".macro", strlen(".macro"))==0 ||
 228                  strncmp(Str, ".if", strlen(".if"))==0 ||
 229                  strncmp(Str, ".align", strlen(".align"))==0 ||
 230                  strncmp(Str, ".fill", strlen(".fill"))==0 ||
 231                  strncmp(Str, ".space", strlen(".space"))==0 ||
 232                  strncmp(Str, ".zerofill", strlen(".zerofill"))==0 ||
 233                  strncmp(Str, ".p2align", strlen(".p2align"))==0 ||
 234                  strncmp(Str, ".p2alignw", strlen(".p2alignw"))==0 ||
 235                  strncmp(Str, ".p2alignl", strlen(".p2alignl"))==0 ||
 236                  strncmp(Str, ".align32", strlen(".p2align32"))==0 ||
 237                  strncmp(Str, ".include", strlen(".include"))==0)
 238           cerr << "Directive " << Str << " in asm may lead to invalid offsets for" <<
 239                    " constant pools (the assembler will tell you if this happens).\n";
 240         // Some generate code, but this is only interesting in the text section.
 241         else if (inTextSection) {
 242           if (strncmp(Str, ".long", strlen(".long"))==0)
 243             Length += 4*countArguments(Str+strlen(".long"));
 244           else if (strncmp(Str, ".short", strlen(".short"))==0)
 245             Length += 2*countArguments(Str+strlen(".short"));
 246           else if (strncmp(Str, ".byte", strlen(".byte"))==0)
 247             Length += 1*countArguments(Str+strlen(".byte"));
 248           else if (strncmp(Str, ".single", strlen(".single"))==0)
 249             Length += 4*countArguments(Str+strlen(".single"));
 250           else if (strncmp(Str, ".double", strlen(".double"))==0)
 251             Length += 8*countArguments(Str+strlen(".double"));
 252           else if (strncmp(Str, ".quad", strlen(".quad"))==0)
 253             Length += 16*countArguments(Str+strlen(".quad"));
 254           else if (strncmp(Str, ".ascii", strlen(".ascii"))==0)
 255             Length += countString(Str+strlen(".ascii"));
 256           else if (strncmp(Str, ".asciz", strlen(".asciz"))==0)
 257             Length += countString(Str+strlen(".asciz"))+1;
 258         }
 259       } else if (inTextSection) {
 260         // An instruction
 261         atInsnStart = false;
 262         if (Subtarget->isThumb()) {
 263           // BL and BLX <non-reg> are 4 bytes, all others 2.
 264           if (strncmp(Str, "blx", strlen("blx"))==0) {
 265             const char* p = Str+3;
 266             while (*p && isspace(*p))
 267               p++;
 268             if (*p == 'r' || *p=='R')
 269               Length += 2;    // BLX reg
 270             else
 271               Length += 4;    // BLX non-reg
 272           } else if (strncmp(Str, "bl", strlen("bl"))==0)
 273             Length += 4;    // BL
 274           else
 275             Length += 2;    // Thumb anything else
 276         }
 277         else
 278           Length += 4;    // ARM
 279       }
 280     }
 281     if (*Str == '\n' || *Str == SeparatorChar)
 282       atInsnStart = true;
 283   }
 284   free(s_copy);
 285   return Length;
 286 }