[Bug inline-asm/36514] New: inline assembly generates wrong code

["codemasterhs at yahoo dot de" <gcc-bugzilla at gcc dot gnu dot org>]

The inline assembly I use in one function generates code which the assembler
does not understand (it generates a non existant cpu register).

This is the commandline output:

Using built-in specs.
Target: i586-elf
Configured with: ../gcc-4.3.1/configure --target=i586-elf --prefix=/usr/cross
--
disable-nls --enable-languages=c,c++ --without-headers --with-newlib
Thread model: single
gcc version 4.3.1 (GCC)
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-S' '-O2' '-mtune=pentium'
 /usr/cross/libexec/gcc/i586-elf/4.3.1/cc1.exe -E -quiet -v gzip.c
-mtune=pentiu
m -O2 -fpch-preprocess -o gzip.i
ignoring nonexistent directory
"/usr/cross/lib/gcc/i586-elf/4.3.1/../../../../i5
86-elf/sys-include"
ignoring nonexistent directory
"/usr/cross/lib/gcc/i586-elf/4.3.1/../../../../i5
86-elf/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/cross/lib/gcc/i586-elf/4.3.1/include
 /usr/cross/lib/gcc/i586-elf/4.3.1/include-fixed
End of search list.
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-S' '-O2' '-mtune=pentium'
 /usr/cross/libexec/gcc/i586-elf/4.3.1/cc1.exe -fpreprocessed gzip.i -quiet
-dum
pbase gzip.c -mtune=pentium -auxbase gzip -O2 -version -o gzip.s
GNU C (GCC) version 4.3.1 (i586-elf)
        compiled by GNU C version 3.4.4 (cygming special, gdc 0.12, using dmd
0.
125), GMP version 4.2.2, MPFR version 2.3.1.
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 51cdd6038f6ef46be90f22b7598c4d3c
In file included from gzip.c:4:
printf.h:9: warning: conflicting types for built-in function 'printf'
printf.h:11: warning: conflicting types for built-in function 'putchar'
COMPILER_PATH=/usr/cross/libexec/gcc/i586-elf/4.3.1/:/usr/cross/libexec/gcc/i586
-elf/4.3.1/:/usr/cross/libexec/gcc/i586-elf/:/usr/cross/lib/gcc/i586-elf/4.3.1/:
/usr/cross/lib/gcc/i586-elf/:/usr/cross/lib/gcc/i586-elf/4.3.1/../../../../i586-
elf/bin/
LIBRARY_PATH=/usr/cross/lib/gcc/i586-elf/4.3.1/:/usr/cross/lib/gcc/i586-elf/4.3.
1/../../../../i586-elf/lib/
COLLECT_GCC_OPTIONS='-v' '-save-temps' '-S' '-O2' '-mtune=pentium'

=================================================================================
This is the .i file:

# 1 "gzip.c"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "gzip.c"
# 1 "gzip.h" 1



# 1 "typedef.h" 1



typedef unsigned char uint8t;
typedef unsigned short uint16t;
typedef unsigned int uint32t;
typedef unsigned long long int uint64t;
# 5 "gzip.h" 2
# 22 "gzip.h"
#pragma pack(1)

struct gzip_hdr_t {
 uint8t id1;
 uint8t id2;
 uint8t cm;
 uint8t flg;
 uint32t mtime;
 uint8t xfl;
 uint8t os;
};

#pragma pack()

uint32t gzipIsGZip(uint8t *file);
uint32t gzipUnzip(uint8t *file, void *dest);
uint8t getNextBit(uint8t *ptr, uint32t *posByte, uint8t *posBit);
# 2 "gzip.c" 2

# 1 "printf.h" 1
# 9 "printf.h"
void printf(char *format, ...);
void printfTrace(char *format, ...);
void putchar(char c);
void putcharTrace(char c);
void itoa(char *str, int num, uint32t base, uint32t flags);
void strreverse(char *begin, char *end);
uint32t getxy();
void setxy(uint32t x, uint32t y);
void scroll_down();
# 4 "gzip.c" 2

uint32t gzipIsGZip(uint8t *file) {
 struct gzip_hdr_t *gzip= (struct gzip_hdr_t *)file;
 if(gzip->id1 != 0x1f)
  return 0;
 if(gzip->id2 != 0x8b)
  return 0;
 if(gzip->cm != 8)
  return 0;
 return 1;
}

uint32t gzipUnzip(uint8t *file, void *dest) {
 struct gzip_hdr_t *gzip= (struct gzip_hdr_t *)file;
 uint8t *ptr, final, type, posBit;
 uint16t crc16, len, *help;
 uint32t posByte;

 if(!gzipIsGZip(file))
  return 0;

 ptr= file + sizeof(struct gzip_hdr_t);

 if(gzip->flg & 0x4) {
  ptr+= (uint16t)*ptr;
 }

 if(gzip->flg & 0x8) {
  while(*ptr != '\0') {
   ptr++;
  }
 }

 if(gzip->flg & 0x10) {
  while(*ptr != '\0') {
   ptr++;
  }
 }

 if(gzip->flg & 0x2) {
  crc16= *ptr;
  ptr++;
 }

 posByte= 0;
 posBit= 0;
 do {
  final= getNextBit(ptr,&posByte,&posBit);
  type= (getNextBit(ptr,&posByte,&posBit) << 1) |
getNextBit(ptr,&posByte,&posBit);
  if(type == 0x3)
   return 0;
  if(type == 0x0) {
   if(posBit != 0) {
    posBit= 0;
    posByte++;
   }
   help= (uint16t *)((uint32t)ptr + posByte);
   len= *help;
  } else {
   if(type == 0x2) {

   }

  }
 }while(!final);

 return 1;
}

uint8t getNextBit(uint8t *ptr, uint32t *posByte, uint8t *posBit) {
 uint8t *help= ptr + *posByte, res;

 asm volatile("testb %2,%1\n\t"
    "setne %0"
    :"=r"(res)
    :"r"(*help),"r"((uint8t)(1 << *posBit)));

 if(*posBit == 7) {
  *posBit= 0;
  (*posByte)++;
 } else {
  (*posBit)++;
 }

 return res;
}


-- 
           Summary: inline assembly generates wrong code
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: inline-asm
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: codemasterhs at yahoo dot de
  GCC host triplet: cygwin
GCC target triplet: i586-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36514