Let the cc compiler help you get started. Compile this program const unsigned int x[5] = {1, 2, 0xdeadbeef, 0xffffffff, 16}; with the -S option to produce assembly output.
For example, this will generate array.s: gcc -S array.c
This will produce a .s file that may look like this:
which gives a starting point that will compile, and can be transformed to become the template, generally with some consulting of as docs and some experimentation.
If you want ICU to automatically use this assembly, you should specify "GENCCODE_ASSEMBLY=-a name" in the specific config/mh-* file, where the name is the compiler or platform that you used in this assemblyHeader data structure.
*/ staticconststruct AssemblyType { constchar *name; constchar *header; constchar *beginLine; constchar *footer;
int8_t hexType; /* HEX_0X or HEX_0h */
} assemblyHeader[] = { /* For gcc assemblers, the meaning of .align changes depending on the */ /* hardware, so we use .balign 16 which always means 16 bytes. */ /* https://sourceware.org/binutils/docs/as/Pseudo-Ops.html */
{"gcc", ".globl %s\n" "\t.section .note.GNU-stack,\"\",%%progbits\n" "#ifdef __CET__\n" "# include \n" "#endif\n" "\t.section .rodata\n" "\t.balign 16\n" "#ifdef U_HIDE_DATA_SYMBOL\n" "\t.hidden %s\n" "#endif\n" "\t.type %s,%%object\n" "%s:\n\n",
if (outFilePath != nullptr) { if (uprv_strlen(buffer.chars) >= outFilePathCapacity) {
fprintf(stderr, "genccode: filename too long\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
uprv_strcpy(outFilePath, buffer.chars); #ifdefined (WINDOWS_WITH_GNUC) && U_PLATFORM != U_PF_CYGWIN /* Need to fix the file separator character when using MinGW. */
swapFileSepChar(outFilePath, U_FILE_SEP_CHAR, '/'); #endif
}
/* turn dashes or dots in the entry name into underscores */
length=uprv_strlen(entry); for(i=0; i<length; ++i) { if(entry[i]=='-' || entry[i]=='.') {
entry[i]='_';
}
}
count = snprintf(
buffer.chars, sizeof(buffer.chars),
assemblyHeader[assemblyHeaderIndex].header,
entry, entry, entry, entry,
entry, entry, entry, entry); if (count >= sizeof(buffer.chars)) {
fprintf(stderr, "genccode: entry name too long (long filename?)\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
T_FileStream_writeLine(out, buffer.chars);
T_FileStream_writeLine(out, assemblyHeader[assemblyHeaderIndex].beginLine);
for(;;) {
memset(buffer.uint32s, 0, sizeof(buffer.uint32s));
length=T_FileStream_read(in, buffer.uint32s, sizeof(buffer.uint32s)); if(length==0) { break;
} for(i=0; i<(length/sizeof(buffer.uint32s[0])); i++) { // TODO: What if the last read sees length not as a multiple of 4?
column = write32(out, buffer.uint32s[i], column);
}
}
T_FileStream_writeLine(out, "\n");
count = snprintf(
buffer.chars, sizeof(buffer.chars),
assemblyHeader[assemblyHeaderIndex].footer,
entry, entry, entry, entry,
entry, entry, entry, entry); if (count >= sizeof(buffer.chars)) {
fprintf(stderr, "genccode: entry name too long (long filename?)\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
T_FileStream_writeLine(out, buffer.chars);
if(T_FileStream_error(in)) {
fprintf(stderr, "genccode: file read error while generating from file %s\n", filename); exit(U_FILE_ACCESS_ERROR);
}
if(T_FileStream_error(out)) {
fprintf(stderr, "genccode: file write error while generating from file %s\n", filename); exit(U_FILE_ACCESS_ERROR);
}
if (outFilePath != nullptr) { if (uprv_strlen(buffer) >= outFilePathCapacity) {
fprintf(stderr, "genccode: filename too long\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
uprv_strcpy(outFilePath, buffer); #ifdefined (WINDOWS_WITH_GNUC) && U_PLATFORM != U_PF_CYGWIN /* Need to fix the file separator character when using MinGW. */
swapFileSepChar(outFilePath, U_FILE_SEP_CHAR, '/'); #endif
}
out=T_FileStream_open(buffer, "w"); if(out==nullptr) {
fprintf(stderr, "genccode: unable to open output file %s\n", buffer); exit(U_FILE_ACCESS_ERROR);
}
/* turn dashes or dots in the entry name into underscores */
length=uprv_strlen(entry); for(i=0; i<length; ++i) { if(entry[i]=='-' || entry[i]=='.') {
entry[i]='_';
}
}
#if U_PLATFORM == U_PF_OS400 /* TODO: Fix this once the compiler implements this feature. Keep in sync with udatamem.c
This is here because this platform can't currently put const data into the read-only pages of an object or shared library (service program). Only strings are allowed in read-only pages, so we use char * strings to store the data.
In order to prevent the beginning of the data from ever matching the magic numbers we must still use the initial double. [grhoten 4/24/2003]
*/
count = snprintf(buffer, sizeof(buffer), "#ifndef IN_GENERATED_CCODE\n" "#define IN_GENERATED_CCODE\n" "#define U_DISABLE_RENAMING 1\n" "#include \"unicode/umachine.h\"\n" "#endif\n" "U_CDECL_BEGIN\n" "const struct {\n" " double bogus;\n" " const char *bytes; \n" "} %s={ 0.0, \n",
entry); if (count >= sizeof(buffer)) {
fprintf(stderr, "genccode: entry name too long (long filename?)\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
T_FileStream_writeLine(out, buffer);
static uint32_t
write32(FileStream *out, uint32_t bitField, uint32_t column) {
int32_t i; char bitFieldStr[64]; /* This is more bits than needed for a 32-bit number */ char *s = bitFieldStr;
uint8_t* ptrIdx = reinterpret_cast<uint8_t*>(&bitField); staticconstchar hexToStr[16] = { '0','1','2','3', '4','5','6','7', '8','9','A','B', 'C','D','E','F'
};
/* write the value, possibly with comma and newline */ if(column==MAX_COLUMN) { /* first byte */
column=1;
} elseif(column<32) {
*(s++)=',';
++column;
} else {
*(s++)='\n';
uprv_strcpy(s, assemblyHeader[assemblyHeaderIndex].beginLine);
s+=uprv_strlen(s);
column=1;
}
if (bitField < 10) { /* It's a small number. Don't waste the space for 0x */
*(s++)=hexToStr[bitField];
} else { int seenNonZero = 0; /* This is used to remove leading zeros */
/* This creates a 32-bit field */ #if U_IS_BIG_ENDIAN for (i = 0; i < sizeof(uint32_t); i++) #else for (i = sizeof(uint32_t)-1; i >= 0 ; i--) #endif
{
uint8_t value = ptrIdx[i]; if (value || seenNonZero) {
*(s++)=hexToStr[value>>4];
*(s++)=hexToStr[value&0xF];
seenNonZero = 1;
}
} if(hexType==HEX_0H) {
*(s++)='h';
}
}
if (status.isFailure()) {
fprintf(stderr, "genccode: error building filename or entrypoint\n"); exit(status.get());
}
if (outFilenameBuilder.length() >= outFilenameCapacity) {
fprintf(stderr, "genccode: output filename too long\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
if (entryNameBuilder.length() >= entryNameCapacity) {
fprintf(stderr, "genccode: entry name too long (long filename?)\n"); exit(U_ILLEGAL_ARGUMENT_ERROR);
}
// link.exe will link an IMAGE_FILE_MACHINE_UNKNOWN data-only .obj file // no matter what architecture it is targeting (though other values are // required to match). Unfortunately, the variable name decoration/mangling // is slightly different on x86, which means we can't use the UNKNOWN type // for all architectures though. # ifdefined(_M_IX86)
*pCPU = IMAGE_FILE_MACHINE_I386; # else // Linker for ClangCL doesn't handle IMAGE_FILE_MACHINE_UNKNOWN the same as // linker for MSVC. Because of this optCpuArch is used to define the CPU // architecture in that case. While _M_AMD64 and _M_ARM64 could be used, // this would potentially be problematic when cross-compiling as this code // would most likely be ran on host machine to generate the .obj file for // the target architecture. # ifdefined(__clang__) if (strcmp(optCpuArch, "x64") == 0) {
*pCPU = IMAGE_FILE_MACHINE_AMD64;
} elseif (strcmp(optCpuArch, "x86") == 0) {
*pCPU = IMAGE_FILE_MACHINE_I386;
} elseif (strcmp(optCpuArch, "arm64") == 0) {
*pCPU = IMAGE_FILE_MACHINE_ARM64;
} else {
std::terminate(); // Unreachable.
} # else
*pCPU = IMAGE_FILE_MACHINE_UNKNOWN; # endif # endif # ifdefined(_M_IA64) || defined(_M_AMD64) || defined (_M_ARM64)
*pBits = 64; // Doesn't seem to be used for anything interesting though? # elif defined(_M_IX86) || defined(_M_ARM)
*pBits = 32; # else # error "Unknown platform for CAN_GENERATE_OBJECTS." # endif #else # error "Unknown platform for CAN_GENERATE_OBJECTS." #endif return;
}
in=T_FileStream_open(filename, "rb"); if(in==nullptr) {
fprintf(stderr, "genccode: unable to open match-arch file %s\n", filename); exit(U_FILE_ACCESS_ERROR);
}
length=T_FileStream_read(in, buffer.bytes, sizeof(buffer.bytes));
#ifdef U_ELF if (length < static_cast<int32_t>(sizeof(Elf32_Ehdr))) {
fprintf(stderr, "genccode: match-arch file %s is too short\n", filename); exit(U_UNSUPPORTED_ERROR);
} if(
buffer.header32.e_ident[0]!=ELFMAG0 ||
buffer.header32.e_ident[1]!=ELFMAG1 ||
buffer.header32.e_ident[2]!=ELFMAG2 ||
buffer.header32.e_ident[3]!=ELFMAG3 ||
buffer.header32.e_ident[EI_CLASS]<ELFCLASS32 || buffer.header32.e_ident[EI_CLASS]>ELFCLASS64
) {
fprintf(stderr, "genccode: match-arch file %s is not an ELF object file, or not supported\n", filename); exit(U_UNSUPPORTED_ERROR);
}
*pBits= buffer.header32.e_ident[EI_CLASS]==ELFCLASS32 ? 32 : 64; /* only 32 or 64: see check above */ #ifdef U_ELF64 if(*pBits!=32 && *pBits!=64) {
fprintf(stderr, "genccode: currently only supports 32-bit and 64-bit ELF format\n"); exit(U_UNSUPPORTED_ERROR);
} #else if(*pBits!=32) {
fprintf(stderr, "genccode: built with elf.h missing 64-bit definitions\n"); exit(U_UNSUPPORTED_ERROR);
} #endif
*pIsBigEndian = static_cast<UBool>(buffer.header32.e_ident[EI_DATA] == ELFDATA2MSB); if(*pIsBigEndian!=U_IS_BIG_ENDIAN) {
fprintf(stderr, "genccode: currently only same-endianness ELF formats are supported\n"); exit(U_UNSUPPORTED_ERROR);
} /* TODO: Support byte swapping */
*pCPU=buffer.header32.e_machine; #elif U_PLATFORM_HAS_WIN32_API if(length<sizeof(IMAGE_FILE_HEADER)) {
fprintf(stderr, "genccode: match-arch file %s is too short\n", filename); exit(U_UNSUPPORTED_ERROR);
} /* TODO: Use buffer.header. Keep aliasing legal. */
pHeader=(const IMAGE_FILE_HEADER *)buffer.bytes;
*pCPU=pHeader->Machine; /* * The number of bits is implicit with the Machine value. * *pBits is ignored in the calling code, so this need not be precise.
*/
*pBits= *pCPU==IMAGE_FILE_MACHINE_I386 ? 32 : 64; /* Windows always runs on little-endian CPUs. */
*pIsBigEndian=false; #else # error "Unknown platform for CAN_GENERATE_OBJECTS." #endif
/* * Use entry[] for the string table which will contain only the * entry point name. * entry[0] must be 0 (NUL) * The entry point name can be up to 38 characters long (sizeof(entry)-2).
*/
/* 16-align .rodata in the .o file, just in case */ staticconstchar padding[16]={ 0 };
int32_t paddingSize;
/* 16-align .rodata in the .o file, just in case */
paddingSize=sectionHeaders32[4].sh_offset & 0xf; if(paddingSize!=0) {
paddingSize=0x10-paddingSize;
sectionHeaders32[4].sh_offset+=paddingSize;
}
/* 16-align .rodata in the .o file, just in case */
paddingSize=sectionHeaders64[4].sh_offset & 0xf; if(paddingSize!=0) {
paddingSize=0x10-paddingSize;
sectionHeaders64[4].sh_offset+=paddingSize;
}
/* set the file header */
objHeader.fileHeader.Machine=cpu;
objHeader.fileHeader.NumberOfSections=2;
objHeader.fileHeader.TimeDateStamp=(DWORD)time(nullptr);
objHeader.fileHeader.PointerToSymbolTable=IMAGE_SIZEOF_FILE_HEADER+2*IMAGE_SIZEOF_SECTION_HEADER+length+size; /* start of symbol table */
objHeader.fileHeader.NumberOfSymbols=1;
/* set the section for the linker options */
uprv_strncpy((char *)objHeader.sections[0].Name, ".drectve", 8);
objHeader.sections[0].SizeOfRawData=length;
objHeader.sections[0].PointerToRawData=IMAGE_SIZEOF_FILE_HEADER+2*IMAGE_SIZEOF_SECTION_HEADER;
objHeader.sections[0].Characteristics=IMAGE_SCN_LNK_INFO|IMAGE_SCN_LNK_REMOVE|IMAGE_SCN_ALIGN_1BYTES;
/* set the data section */
uprv_strncpy((char *)objHeader.sections[1].Name, ".rdata", 6);
objHeader.sections[1].SizeOfRawData=size;
objHeader.sections[1].PointerToRawData=IMAGE_SIZEOF_FILE_HEADER+2*IMAGE_SIZEOF_SECTION_HEADER+length;
objHeader.sections[1].Characteristics=IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_ALIGN_16BYTES|IMAGE_SCN_MEM_READ;
/* set the symbol table */ if(entryLength<=8) {
uprv_strncpy((char *)symbols[0].N.ShortName, entry, entryLength);
symbolNames.sizeofLongNames=4;
} else {
symbols[0].N.Name.Short=0;
symbols[0].N.Name.Long=4;
symbolNames.sizeofLongNames=4+entryLength+1;
uprv_strcpy(symbolNames.longNames, entry);
}
symbols[0].SectionNumber=2;
symbols[0].StorageClass=IMAGE_SYM_CLASS_EXTERNAL;
/* write the file header and the linker options section */
T_FileStream_write(out, &objHeader, objHeader.sections[1].PointerToRawData); #else # error "Unknown platform for CAN_GENERATE_OBJECTS." #endif
/* copy the data file into section 2 */ for(;;) {
length=T_FileStream_read(in, buffer, sizeof(buffer)); if(length==0) { break;
}
T_FileStream_write(out, buffer, length);
}
#if U_PLATFORM_HAS_WIN32_API /* write the symbol table */
T_FileStream_write(out, symbols, IMAGE_SIZEOF_SYMBOL);
T_FileStream_write(out, &symbolNames, symbolNames.sizeofLongNames); #endif
if(T_FileStream_error(in)) {
fprintf(stderr, "genccode: file read error while generating from file %s\n", filename); exit(U_FILE_ACCESS_ERROR);
}
if(T_FileStream_error(out)) {
fprintf(stderr, "genccode: file write error while generating from file %s\n", filename); exit(U_FILE_ACCESS_ERROR);
}
Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.
Bemerkung:
Die farbliche Syntaxdarstellung und die Messung sind noch experimentell.