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Re: powerpc & unaligned block moves with fp registers
- To: dje at watson dot ibm dot com
- Subject: Re: powerpc & unaligned block moves with fp registers
- From: DJ Delorie <dj at redhat dot com>
- Date: Thu, 1 Nov 2001 16:03:07 -0500
- CC: gcc at gcc dot gnu dot org
- References: <200111012026.PAA25118@makai.watson.ibm.com>
> > What is your definition of "unaligned"? Anything other than
> > natural alignment?
>
> The intent is "anything that causes a trap".
Here's an example:
typedef struct {
char a[8];
} X;
static char v[1] = { 3 };
static X i = {1}, j = {2};
foo()
{
i = j;
}
./cc1 -quiet -O2 -mno-strict-align dj.c
trimmed output:
.section ".data"
.align 2
v:
.byte 3
i:
.byte 1
.space 7
j:
.byte 2
.space 7
.section ".text"
.align 2
foo:
lis 9,j@ha
la 9,j@l(9)
lfd 0,0(9)
lis 9,i@ha
la 9,i@l(9)
stfd 0,0(9)
blr