On Wed, 30 Jan 2019, Mark Cave-Ayland wrote:
On 29/01/2019 23:05, Richard Henderson wrote:
On 1/29/19 11:17 AM, Mark Cave-Ayland wrote:
+#define VMRG_DO(name, element, access, ofs) \
void helper_v##name(ppc_avr_t *r, ppc_avr_t *a, ppc_avr_t *b) \
{ \
ppc_avr_t result; \
int i; \
\
+ for (i = 0; i < ARRAY_SIZE(r->element) / 2; i++) { \
+ result.access(i * 2 + 0) = a->access(i + ofs); \
+ result.access(i * 2 + 1) = b->access(i + ofs); \
} \
*r = result; \
}
+
+#define VMRG(suffix, element, access, half) \
+ VMRG_DO(mrgl##suffix, element, access, half) \
+ VMRG_DO(mrgh##suffix, element, access, 0)
+VMRG(b, u8, VsrB, 8)
+VMRG(h, u16, VsrH, 4)
+VMRG(w, u32, VsrW, 2)
So... the point of "half" was to not replicate knowledge out to VMRG.
Just use
int i, half = ARRAY_SIZE(r->element) / 2;
for (i = 0; i < half; i++) {
within VMRG_DO.
Okay - I was a bit confused because in your example macro signature you added
ofs
which made me think you wanted its value to be determined outside, but never
mind.
What about the following instead? With high set as part of the macro then the
initial
assignment to ofs should be inlined accordingly at compile time:
#define VMRG_DO(name, element, access, high) \
void helper_v##name(ppc_avr_t *r, ppc_avr_t *a, ppc_avr_t *b) \
{ \
ppc_avr_t result; \
int ofs, half = ARRAY_SIZE(r->element) / 2; \
int i; \
\
if (high) { \
ofs = 0; \
} else { \
ofs = half; \
} \
This could be also written as:
int i, half = ARRAY_SIZE(r->element) / 2; \
int ofs = (high ? 0 : half); \
to save a few lines but it depends on personal taste which one is more
readable for someone.
Regards,
BALATON Zoltan
\
for (i = 0; i < half; i++) { \
result.access(i * 2 + 0) = a->access(i + ofs); \
result.access(i * 2 + 1) = b->access(i + ofs); \
} \
*r = result; \
}
#define VMRG(suffix, element, access) \
VMRG_DO(mrgl##suffix, element, access, 0) \
VMRG_DO(mrgh##suffix, element, access, 1)
VMRG(b, u8, VsrB)
VMRG(h, u16, VsrH)
VMRG(w, u32, VsrW)
#undef VMRG_DO
#undef VMRG
#undef VMRG
ATB,
Mark.
