6502
/
cc65
mirror of https://github.com/cc65/cc65.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Optimize unsigned int and long > 255

This commit is contained in:
Colin Leroy-Mira 2023-11-17 22:49:03 +01:00
parent d7d1d89698
commit 3066b1f9b4
2 changed files with 98 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
src/cc65/codegen.c
View File

@ -4199,10 +4199,14 @@ void g_gt (unsigned flags, unsigned long val)
*/
g_ne (flags, val);
} else if (val < 0xFFFF) {
/* Use >= instead of > because the former gives better
** code on the 6502 than the latter.
*/
g_ge (flags, val+1);
if (val == 0xFF) {
AddCodeLine ("cpx #$00");
} else {
/* Use >= instead of > because the former gives better
** code on the 6502 than the latter.
*/
g_ge (flags, val+1);
}
} else {
/* Never true */
Warning ("Condition is never true");
@ -4229,6 +4233,8 @@ void g_gt (unsigned flags, unsigned long val)
** is easier to optimize.
*/
g_ne (flags, val);
} else if (val == 0xFF) {
AddCodeLine ("cpx #$00");
} else if (val < 0xFFFFFFFF) {
/* Use >= instead of > because the former gives better
** code on the 6502 than the latter.
@ -4241,7 +4247,9 @@ void g_gt (unsigned flags, unsigned long val)
}
} else {
/* Signed compare */
if ((long) val < 0x7FFFFFFF) {
if (val == 0xFF) {
AddCodeLine ("cpx #$00");
} else if ((long) val < 0x7FFFFFFF) {
g_ge (flags, val+1);
} else {
/* Never true */

85
test/val/compare8.c
View File

@ -23,6 +23,8 @@ bit bit0 = 0;
#endif
int int0 = 0;
int int1 = 0;
unsigned int uint0 = 0;
unsigned int uint1 = 0;
unsigned char uchar0 = 0;
unsigned char uchar1 = 0;
signed char char0 = 0;
@ -296,12 +298,95 @@ void int_compare2(void)
c_int_gt_lit2(0xff);
}
void c_uint_gt_lit1(unsigned char expected_result)
{
result = 0;
if(uint0 > 0)
result |= 1;
if(uint0 > 1)
result |= 2;
if(uint0 > 0xff)
result |= 4;
if(uint0 > 0x100)
result |= 8;
if(uint0 > 0x0101)
result |= 0x10;
if(uint0 > 0x01ff)
result |= 0x20;
if(uint0 > 0x0200)
result |= 0x40;
if(uint0 > 0x0201)
result |= 0x80;
if(result != expected_result)
failures=1;
}
void uint_compare1(void)
{
uint0 = 0;
c_uint_gt_lit1(0x00);
uint0 = 1;
c_uint_gt_lit1(0x01);
uint0 = 2;
c_uint_gt_lit1(0x03);
uint0 = 0xfe;
c_uint_gt_lit1(0x03);
uint0 = 0xff;
c_uint_gt_lit1(0x03);
uint0 = 0x100;
c_uint_gt_lit1(0x07);
uint0 = 0x101;
c_uint_gt_lit1(0x0f);
uint0 = 0x102;
c_uint_gt_lit1(0x1f);
uint0 = 0x1fe;
c_uint_gt_lit1(0x1f);
uint0 = 0x1ff;
c_uint_gt_lit1(0x1f);
uint0 = 0x200;
c_uint_gt_lit1(0x3f);
uint0 = 0x201;
c_uint_gt_lit1(0x7f);
uint0 = 0x7f00;
c_uint_gt_lit1(0xff);
/* now check contiguous ranges */
for(uint0 = 2; uint0 != 0xff; uint0++)
c_uint_gt_lit1(0x03);
for(uint0 = 0x202; uint0 != 0xffff; uint0++)
c_uint_gt_lit1(0xff);
}
int
main (void)
{
char_compare();
int_compare1();
int_compare2();
uint_compare1();
success = failures;
done ();