egcs-2.91.66 PPC register bug

[Ralph Schmidt]

 Though a register content is defined as unsigned and a target variable
is also marked unsigned it creates a signed value.

P.S. Is it possible after 2.95 to discuss some PPC optimizer misses
        as you all seem to be very busy at the moment with the 2.95 release ?

################################################
struct  Fubar
{
        signed char     A;
};

register unsigned int   REG_PTR         __asm("25");
register unsigned int   REG_A           __asm("16");

void    Test4(void)
{
unsigned int    A;
  A     =(unsigned int) (((struct Fubar*)REG_PTR)->A);
  REG_A =       A;
}

results into this program

        .file   "test.c"

 # rs6000/powerpc options: -msdata=data -G 8
 # options passed:  -mregnames -O2 -fverbose-asm
 # options enabled:  -fdefer-pop -fomit-frame-pointer -fcse-follow-jumps
 # -fcse-skip-blocks -fexpensive-optimizations -fthread-jumps
 # -fstrength-reduce -fpeephole -fforce-mem -ffunction-cse -finline
 # -fkeep-static-consts -fcaller-saves -fpcc-struct-return -fgcse
 # -frerun-cse-after-loop -frerun-loop-opt -fschedule-insns
 # -fschedule-insns2 -fsched-interblock -fsched-spec -fsjlj-exceptions
 # -fcommon -fverbose-asm -fgnu-linker -fregmove -foptimize-register-move
 # -fargument-alias -mpowerpc -mnew-mnemonics -mregnames -mcall-sysv
 # -msdata=data

gcc2_compiled.:
        .section        ".text"
        .align 2
        .globl Test4
        .type    Test4,@function
Test4:
        lbz %r0,0(%r25)
        extsb %r16,%r0
	***************** In my eyes this is wrong.
        blr
.Lfe1:
        .size    Test4,.Lfe1-Test4
        .ident  "GCC: (GNU) egcs-2.91.66 19990314 (egcs-1.1.2 release)"


---
Ralph Schmidt,laire@popmail.owl.de(private),NextMail welcome