[Bug inline-asm/47419] New: missed 'mov (base,index,scale),reg' optimization?

[pluto at agmk dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47419

           Summary: missed 'mov (base,index,scale),reg' optimization?
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: inline-asm
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: pl...@agmk.net


following code...

unsigned __attribute__((regparm(2)))
asm_read_mapped_register( unsigned* address, unsigned long index )
{
        unsigned value;
        asm /* reading has side-effects in hardware */ volatile (
                "movl (%1), %0"
                : /* output operands */ "=r" ( value )
                : /* input operands */ "r" ( address + index )
                : /* clobbers */
        );
        return value;
}

produces...

asm_read_mapped_register:
        leaq (%rdi,%rsi,4), %rax
        movl (%rax), %eax
        ret

is it a bug in asm inline? why the 'movl (%rdi,%rsi,4),%eax' isn't emitted?