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Special code for signed compares against zero

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git-svn-id: svn://svn.cc65.org/cc65/trunk@2692 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2003-11-29 06:56:24 +00:00
parent 8f9a21ae3f
commit add702a2f0
1 changed files with 66 additions and 7 deletions
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73
src/cc65/codegen.c
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@ -7,7 +7,7 @@
/* */
/* */
/* (C) 1998-2003 Ullrich von Bassewitz */
/* Römerstrasse 52 */
/* Römerstraße 52 */
/* D-70794 Filderstadt */
/* EMail: uz@cc65.org */
/* */
@ -283,7 +283,7 @@ unsigned sizeofarg (unsigned flags)
}
int pop (unsigned flags)
/* Pop an argument of the given size */
{
@ -2780,7 +2780,7 @@ void g_or (unsigned flags, unsigned long val)
/* FALLTHROUGH */
case CF_INT:
if (val <= 0xFF) {
if (val <= 0xFF) {
if ((val & 0xFF) != 0) {
AddCodeLine ("ora #$%02X", (unsigned char)val);
}
@ -2900,7 +2900,7 @@ void g_and (unsigned Flags, unsigned long Val)
0, 0, "tosandeax",
0, 0, "tosandeax",
};
/* If the right hand side is const, the lhs is not on stack but still
* in the primary register.
*/
@ -2973,7 +2973,7 @@ void g_and (unsigned Flags, unsigned long Val)
Flags &= ~CF_FORCECHAR;
g_push (Flags & ~CF_CONST, 0);
}
/* Use long way over the stack */
oper (Flags, Val, ops);
}
@ -3550,7 +3550,8 @@ void g_lt (unsigned flags, unsigned long val)
if (flags & CF_CONST) {
/* Because the handling of the overflow flag is too complex for
* inlining, we can handle only unsigned compares here.
* inlining, we can handle only unsigned compares, and signed
* compares against zero here.
*/
if (flags & CF_UNSIGNED) {
@ -3600,6 +3601,34 @@ void g_lt (unsigned flags, unsigned long val)
typeerror (flags);
}
} else if (val == 0) {
/* Look at the type */
switch (flags & CF_TYPE) {
case CF_CHAR:
if (flags & CF_FORCECHAR) {
AddCodeLine ("tax");
AddCodeLine ("jsr boollt");
return;
}
/* FALLTHROUGH */
case CF_INT:
/* Just check the high byte */
AddCodeLine ("txa");
AddCodeLine ("jsr boollt");
return;
case CF_LONG:
/* Just check the high byte */
AddCodeLine ("lda sreg+1");
AddCodeLine ("jsr boollt");
return;
default:
typeerror (flags);
}
}
/* If we go here, we didn't emit code. Push the lhs on stack and fall
@ -3885,7 +3914,8 @@ void g_ge (unsigned flags, unsigned long val)
if (flags & CF_CONST) {
/* Because the handling of the overflow flag is too complex for
* inlining, we can handle only unsigned compares here.
* inlining, we can handle only unsigned compares, and signed
* compares against zero here.
*/
if (flags & CF_UNSIGNED) {
@ -3935,8 +3965,37 @@ void g_ge (unsigned flags, unsigned long val)
typeerror (flags);
}
} else if (val == 0) {
/* Look at the type */
switch (flags & CF_TYPE) {
case CF_CHAR:
if (flags & CF_FORCECHAR) {
AddCodeLine ("tax");
AddCodeLine ("jsr boolge");
return;
}
/* FALLTHROUGH */
case CF_INT:
/* Just test the high byte */
AddCodeLine ("txa");
AddCodeLine ("jsr boolge");
return;
case CF_LONG:
/* Just test the high byte */
AddCodeLine ("lda sreg+1");
AddCodeLine ("jsr boolge");
return;
default:
typeerror (flags);
}
}
/* If we go here, we didn't emit code. Push the lhs on stack and fall
* into the normal, non-optimized stuff. Note: The standard stuff will
* always work with ints.