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
