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