The code of PeepHoleOptimization is now big enough that it triggers bogus "Relative address out of range" range errors from the linker. This is a linker bug and should be fixed there.
When an expression that the intermediate code peephole optimizer could reduce to a constant was cast to a char type, the resulting value could be outside the range of that type.
The following program illustrates the problem:
#pragma optimize 1
#include <stdio.h>
int main(void) {
int i = 0;
i = (unsigned char)(i | -1);
printf("%i\n", i);
}
This includes:
*Functions operating on long long in <stdlib.h>
*Limits of long long types in <limits.h>
*64-bit types and limits (plus intmax_t and its limits) in <stdint.h>
*New format codes, plus functions operating on intmax_t, in <inttypes.h>
The new stuff is generally conditionalized to only be included if __ORCAC_HAS_LONG_LONG__ is defined, or if the implementation claims to be C99 or later. This allows the headers to remain usable with older versions of ORCA/C, or with any hypothetical "strict C89" mode that might be implemented in the future.
*Recognize the 'll' and 'j' size modifiers as denoting long long times.
*Recognize '%P' as equivalent to '%b'.
*Give a warning for 'L' length modifier in scanf, which is currently not supported (except when assignment is suppressed).
The changes to constant expressions were not allowing the unsupported constant expressions to be evaluated at run time when they appear in regular code.
This makes it more likely that unsupported ops on long long or any other types added in the future will give an error rather than silently generating bad code.
Also, update a comment.
This affected initializers like the following:
static int a[50];
static int *ip = &a[0] + 2U;
Also, introduce some basic range checks for calculations that are obviously outside the 65816's address space.
This has no functional effect, since it is all comments. It does mean that printed listings of CGI.pas would not contain those comments, but it is easy enough to restore if someone wants such listings.
This change should make compilation slightly faster, and it also avoids issues with filetypes when using certain tools (since they cannot infer the filetype of CGI.Comments from its extension).
This was previously happening in intermediate code peephole optimization.
The following example program demonstrates the problem:
#pragma optimize 1
int main(void) {
int i = 0;
long j = 0;
++i | -1;
++i & 0;
++j | -1;
++j & 0;
return i+j; /* should be 4 */
}
These involve recent standards-conformance patches for printf and scanf, which changed some (non-standard) behaviors that the test cases were expecting.
I also fixed a couple things that clang flagged as undefined behavior, even though they weren't really causing problems under ORCA/C.
These use a new calling convention specific to functions returning these types. When such functions are called, the caller must set the X register to the address within bank 0 that the return value is to be saved to. The function is then responsible for saving it there before returning to the caller.
Currently, the calling code always makes space for the return value on the stack and sets X to point to that. (As an optimization, it would be possible to have the return value written directly to a local variable on the direct page, with no change needed to the function being called, but that has not yet been implemented.)
This converts them to 32-bit values before doing computations, which is (more than) sufficient for address calculations on the 65816. Trying to compute an address outside the legal range is undefined behavior, and does not necessarily "wrap around" in a predictable way.
