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vvp: `%{concati,pushi}/vec4` use `get_immediate_rval()` helper 

Both the `%concati/vec4` and `%pushi/vec4` instructions need to construct a
vector from the immediate value encoded in the instruction. Currently both
these instructions have a custom implementation for that.

Remove the custom implementations from those functions and use the
`get_immediate_rval()` helper function. This removes a bit of duplicated
code.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
This commit is contained in:
Lars-Peter Clausen 2022-05-28 10:01:09 +02:00
parent e8cc9f3721
commit 07378fd300
1 changed files with 2 additions and 84 deletions
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86
vvp/vthread.cc
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@ -2350,8 +2350,6 @@ bool of_CONCAT_VEC4(vthread_t thr, vvp_code_t)
*/
bool of_CONCATI_VEC4(vthread_t thr, vvp_code_t cp)
{
uint32_t vala = cp->bit_idx[0];
uint32_t valb = cp->bit_idx[1];
unsigned wid = cp->number;
vvp_vector4_t&msb = thr->peek_vec4();
@ -2360,38 +2358,7 @@ bool of_CONCATI_VEC4(vthread_t thr, vvp_code_t cp)
// going to be zero, so start the result vector with all zero
// bits. Then we only need to replace the bits that are different.
vvp_vector4_t lsb (wid, BIT4_0);
// The %concati/vec4 can create values bigger then 32 bits, but
// only if the high bits are zero. So at most we need to run
// through the loop below 32 times. Maybe less, if the target
// width is less. We don't have to do anything special on that
// because vala/valb bits will shift away so (vala|valb) will
// turn to zero at or before 32 shifts.
for (unsigned idx = 0 ; idx < wid && (vala|valb) ; idx += 1) {
uint32_t ba = 0;
// Convert the vala/valb bits to a ba number that can be
// used to select what goes into the value.
ba = (valb & 1) << 1;
ba |= vala & 1;
switch (ba) {
case 1:
lsb.set_bit(idx, BIT4_1);
break;
case 2:
lsb.set_bit(idx, BIT4_Z);
break;
case 3:
lsb.set_bit(idx, BIT4_X);
break;
default:
break;
}
vala >>= 1;
valb >>= 1;
}
get_immediate_rval (cp, lsb);
vvp_vector4_t res (msb.size()+lsb.size(), BIT4_X);
res.set_vec(0, lsb);
@ -5095,62 +5062,13 @@ bool of_PUSHI_STR(vthread_t thr, vvp_code_t cp)
*/
bool of_PUSHI_VEC4(vthread_t thr, vvp_code_t cp)
{
uint32_t vala = cp->bit_idx[0];
uint32_t valb = cp->bit_idx[1];
unsigned wid = cp->number;
// I expect that most of the bits of an immediate value are
// going to be zero, so start the result vector with all zero
// bits. Then we only need to replace the bits that are different.
vvp_vector4_t val (wid, BIT4_0);
// Special case: Immediate zero is super easy.
if (vala==0 && valb==0) {
thr->push_vec4(val);
return true;
}
// Special case: If the value is defined (no X or Z) and fits
// in an unsigned long, then use the setarray method to write
// the value all in one shot.
if ((valb==0) && (wid <= 8*sizeof(unsigned long))) {
unsigned long tmp = vala;
val.setarray(0, wid, &tmp);
thr->push_vec4(val);
return true;
}
// The %pushi/vec4 can create values bigger then 32 bits, but
// only if the high bits are zero. So at most we need to run
// through the loop below 32 times. Maybe less, if the target
// width is less. We don't have to do anything special on that
// because vala/valb bits will shift away so (vala|valb) will
// turn to zero at or before 32 shifts.
for (unsigned idx = 0 ; idx < wid && (vala|valb) ; idx += 1) {
uint32_t ba = 0;
// Convert the vala/valb bits to a ba number that can be
// used to select what goes into the value.
ba = (valb & 1) << 1;
ba |= vala & 1;
switch (ba) {
case 1:
val.set_bit(idx, BIT4_1);
break;
case 2:
val.set_bit(idx, BIT4_Z);
break;
case 3:
val.set_bit(idx, BIT4_X);
break;
default:
break;
}
vala >>= 1;
valb >>= 1;
}
get_immediate_rval (cp, val);
thr->push_vec4(val);