Here is a 20 % increase code size, because the compiler tries too much to
jump to UI_plotHline() instead of just calling the function and then doing
a standard return at the end of drawbutton()...
[EMAIL PROTECTED] projet]$ cat tmp.c
typedef struct {
unsigned short x, y; /* x should be the easyest to read */
} __attribute__ ((packed)) coord;
extern inline void
UI_plotHline (coord xy, unsigned short xend, unsigned color) {
extern UI_function_plotHline (coord xy, unsigned xend, unsigned color);
UI_function_plotHline (xy, xend, color);
}
extern inline void
UI_setpixel (coord xy, unsigned color) {
extern UI_function_setpixel (coord xy, unsigned color);
UI_function_setpixel (xy, color);
}
extern inline void bound_stack (void)
{
/*
* limit included - but add 2 to high limit for reg16, and 4 for reg32
* if not in bound, exception #BR generated (INT5).
* iret from INT5 will retry the bound instruction.
*/
extern unsigned STATE_stack_limit;
asm volatile (" bound %%esp,%0 " : : "m" (STATE_stack_limit) );
}
void
drawbutton (coord upperleft, coord lowerright,
unsigned upperleftcolor, unsigned lowerrightrcolor,
unsigned fillcolor, unsigned drawbackground)
{bound_stack();{
/* Enlarge the button by few pixels: */
upperleft.x -= 2;
lowerright.x += 2;
lowerright.y -= 1; /* do not overlap two consecutive lines */
UI_plotHline (upperleft, lowerright.x, upperleftcolor); /* top line */
/* do not change VESA1 banks too often, process horizontally,
left to right, line per line */
for (;;) {
upperleft.y += 1;
if (upperleft.y >= lowerright.y)
break;
UI_setpixel (upperleft, upperleftcolor);
if (drawbackground)
UI_plotHline (((coord) { .x = upperleft.x + 1, .y = upperleft.y }),
lowerright.x - 1, fillcolor);
UI_setpixel (((coord) { .x = lowerright.x - 1, .y = upperleft.y }),
lowerrightrcolor);
}
UI_plotHline (upperleft, lowerright.x, lowerrightrcolor); /* bottom line
*/
}}
[EMAIL PROTECTED] projet]$ gcc -v
Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man
--infodir=/usr/share/info --enable-shared --enable-threads=posix
--enable-checking=release --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-libgcj-multifile
--enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk
--disable-dssi --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre
--with-cpu=generic --host=i386-redhat-linux
Thread model: posix
gcc version 4.1.0 20060304 (Red Hat 4.1.0-3)
[EMAIL PROTECTED] projet]$ gcc -Os -c tmp.c && size *.o
text data bss dec hex filename
276 0 0 276 114 tmp.o
[EMAIL PROTECTED] projet]$ toolchain-3.4.5/bin/gcc -v
Reading specs from
/home/etienne/projet/toolchain-3.4.5/bin/../lib/gcc/i686-pc-linux-gnu/3.4.5/specs
Configured with: ../configure --prefix=/home/etienne/projet/toolchain
--enable-languages=c
Thread model: posix
gcc version 3.4.5
[EMAIL PROTECTED] projet]$ toolchain-3.4.5/bin/gcc -Os -c tmp.c && size *.o
text data bss dec hex filename
227 0 0 227 e3 tmp.o
[EMAIL PROTECTED] projet]$
--
Summary: 20 % increase code size in 4.1 vs 3.4.5, tail return
optimisation
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: etienne_lorrain at yahoo dot fr
GCC build triplet: i386-redhat-linux
GCC host triplet: i386-redhat-linux
GCC target triplet: i386-redhat-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27357
