assembly in future C standard HCF Gerry Wheeler


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  • 1. Is this code totaly a shit?
    Probably shit is better than this code? ------------- #include <stdio.h> #include <string.h> void UppStrg(char *Low, char *Upp, int cnt) ; int main(void) { int n = 40 ; char Txt1[n] ; char Txt2[n] ; int i ; printf("\n\nThis program reads and converts : 1- a lower case string into upper case : \n") ; do { printf("\nEnter a lowercase string : \n") ; scanf("%s", Txt1) ; n = strlen(Txt1) ; for ( i = 0 ; i <= n ; i++ ) { if ( (Txt1[i] <= 'a' ) || (Txt1[i] >= 'z') ) /* IF checks if there are any characters other than lowercase letters */ printf("\nThere are no lowercase letters in this string !\n\n") ; else UppStrg(&Txt1[i], &Txt2[i], n) ; } } while ( (Txt1[i] <= 97 ) && (Txt1[i] >= 123) ) ; for ( i = 0 ; i <= n ; i++ ) putchar(Txt2[i]) ; printf("\n\n") ; return 0 ; } /* Function that should move a lowercase letter into uppercase */ void UppStrg(char *Low, char *Upp, int cnt) { int i ; for ( i = 0 ; i <= cnt ; cnt++ ) *(Upp+i) = *(Low+i) - 'a' + 'A'; }

Re: assembly in future C standard HCF Gerry Wheeler

Postby Walter Banks » Sat, 04 Nov 2006 22:35:39 GMT

As this thread wanders off topic this industry was introduced to a new
mnemonic in Byte article about decoding the undocumented
Motorola 6800 instructions. The HCF (Halt Catch Fire) opcode $DD
or $D9. HFC locked up the processor and cycled the address bus
The author of that article was Gerry Wheeler.

Gerry Wheeler, 54, died October 15, 2006, advanced non-Hodgkins
lymphoma cancer. Gerry made significant contributions to the technology
of the embedded systems world and was a key part of the development
of many household name products.

Programmer, Ham KG4NBB, author, father, husband, active commuity
participant Gerry will be missed by all.


Similar Threads:

1.assembly in future C standard

Peter Nilsson < XXXX@XXXXX.COM > wrote:

(Crossposted to comp.std.c, with followups directed there, hopefully
 appropriately.  The original post discussed the possibility of whether
 __asm or something similar to it would be added to the C standard.)

> Contrary to Richard Heathfield's categorical statement, it is not an
> absolute given that there will never be an asm keyword in C. But it
> is unlikely because it's already clear that the asm keyword in C++ has
> not served to truly standardise the syntax of inline assembly.

One idea that was not mentioned in the original thread (I imagine for
good reason, because it's a half-baked and probably stupid idea that
occurred to me reading your post) would be to allow for some kind of
conditional assembly, just perhaps something like

#pragma assemble
#pragma X86 /* Inner pragma's implementation-defined */
  /* Inline assembly, which the implementation can ignore or not */
#pragma no-assemble
  /* Stock C code for implementations that can't or won't accept the
   * assemble pragma: */
  for( i=1; i < 10; i++ ) {
    /* ... */
#pragma end-assemble

The end result would be something like "If the implementation attempts
to inline the assembly code contained within a #pragma assemble
directive, the behavior is implementation-defined.  Otherwise the
assembly code shall be ignored and the C code contained within any
corresponding #pragma no-assemble directive shall be compiled as
though no directives were present."  It would require adding some
duties to the #pragma directive, but it would allow implementors to
take a reasonable shot at using targetted assembly instructions when
appropriate and available, and reverting to ordinary C otherwise.

I'm sure there are reasons why this is stupid and/or impossible, or it
would have been done already :-)

> At the end of the day, the committee could probably spend many man
> weeks deciding issues on an __asm keyword, but for what? Most
> implementations will keep their existing syntax, and most programmers
> who use inline assembly will no doubt continue to prefer the localised
> syntax because it's less cumbersome than any standard syntax.

Indeed, but it's an interesting thought experiment to consider how the
committee *might* add assembly to C if they chose to do so.  (Well,
interesting to me, at least.)

C. Benson Manica           | I *should* know what I'm talking about - if I
cbmanica(at)      | don't, I need to know.  Flames welcome.

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