On 12/3/21 5:00 AM, Richard Henderson wrote:
On 11/12/21 6:14 AM, matheus.fe...@eldorado.org.br wrote:
From: Matheus Ferst <matheus.fe...@eldorado.org.br>
Implement the following PowerISA v3.1 instructions:
vextractbm: Vector Extract Byte Mask
vextracthm: Vector Extract Halfword Mask
vextractwm: Vector Extract Word Mask
vextractdm: Vector Extract Doubleword Mask
vextractqm: Vector Extract Quadword Mask
Suggested-by: Richard Henderson <richard.hender...@linaro.org>
Signed-off-by: Matheus Ferst <matheus.fe...@eldorado.org.br>
---
v2:
- Applied rth suggestion to do_vextractm
---
target/ppc/insn32.decode | 6 +++
target/ppc/translate/vmx-impl.c.inc | 60 +++++++++++++++++++++++++++++
2 files changed, 66 insertions(+)
diff --git a/target/ppc/insn32.decode b/target/ppc/insn32.decode
index 9a28f1d266..639ac22bf0 100644
--- a/target/ppc/insn32.decode
+++ b/target/ppc/insn32.decode
@@ -419,6 +419,12 @@ VEXPANDWM 000100 ..... 00010 ..... 11001000010
@VX_tb
VEXPANDDM 000100 ..... 00011 ..... 11001000010 @VX_tb
VEXPANDQM 000100 ..... 00100 ..... 11001000010 @VX_tb
+VEXTRACTBM 000100 ..... 01000 ..... 11001000010 @VX_tb
+VEXTRACTHM 000100 ..... 01001 ..... 11001000010 @VX_tb
+VEXTRACTWM 000100 ..... 01010 ..... 11001000010 @VX_tb
+VEXTRACTDM 000100 ..... 01011 ..... 11001000010 @VX_tb
+VEXTRACTQM 000100 ..... 01100 ..... 11001000010 @VX_tb
+
# VSX Load/Store Instructions
LXV 111101 ..... ..... ............ . 001 @DQ_TSX
diff --git a/target/ppc/translate/vmx-impl.c.inc
b/target/ppc/translate/vmx-impl.c.inc
index 58aca58f0f..dd7337c2f2 100644
--- a/target/ppc/translate/vmx-impl.c.inc
+++ b/target/ppc/translate/vmx-impl.c.inc
@@ -1539,6 +1539,66 @@ static bool trans_VEXPANDQM(DisasContext *ctx, arg_VX_tb
*a)
return true;
}
+static bool do_vextractm(DisasContext *ctx, arg_VX_tb *a, unsigned vece)
+{
+ const uint64_t elem_width = 8 << vece, elem_count_half = 8 >> vece;
+ TCGv_i64 t, b, tmp;
+
+ REQUIRE_INSNS_FLAGS2(ctx, ISA310);
+ REQUIRE_VECTOR(ctx);
+
+ t = tcg_const_i64(0);
+ b = tcg_temp_new_i64();
+ tmp = tcg_temp_new_i64();
+
+ for (int w = 0; w < 2; w++) {
+ get_avr64(b, a->vrb, w);
+
+ for (int i = 0; i < elem_count_half; i++) {
+ int in_bit = (i + 1) * elem_width - 1;
+ int out_bit = w * elem_count_half + i;
+
+ if (in_bit > out_bit) {
+ tcg_gen_shri_i64(tmp, b, in_bit - out_bit);
+ } else {
+ tcg_gen_shli_i64(tmp, b, out_bit - in_bit);
+ }
+ tcg_gen_andi_i64(tmp, tmp, 1 << out_bit);
+ tcg_gen_or_i64(t, t, tmp);
+ }
+ }
+ tcg_gen_trunc_i64_tl(cpu_gpr[a->vrt], t);
Pardon me. I realized after the fact that we can run the same algorithm as for mtvsrm (in
the next patch) in reverse.
& dup(1)
.......a.......b.......c.......d.......e.......f.......g.......h
>> 32 - 4
...................................a.......b.......c.......d....
|
.......a.......b.......c.......d...a...e...b...f...c...g...d...h
>> 16 - 2
.....................a.......b.......c.......d...a...e...b...f..
|
.......a.......b.....a.c.....b.d...a.c.e...b.d.f.a.c.e.g.b.d.f.h
>> 8 - 1
..............a.......b.....a.c.....b.d...a.c.e...b.d.f.a.c.e.g.
|
.......a......ab.....abc....abcd...abcde..abcdef.abcdefgabcdefgh
& 0xff
........................................................abcdefgh
where one of the two final masks can be done via deposit:
tcg_gen_andi_i64(hi, hi, 0xff);
tcg_gen_deposit_i64(lo, lo, hi, 8, 56);
Which will reduce the instruction count of this implementation by half.
Oops, ENOCOFFEE. Of course the input bit comes from the msb of the element, not the lsb.
Three different options:
(1) Begin with a shift of elem_count_half - 1, then do the above,
(2) Change the initial mask to the msb, then extract from elem_count_half - 1.
(3) Do left shifts so that we collect the bits at the msb of
the word. This probably results in the easiest concatenation
in the end:
tcg_gen_shri_i64(hi, hi, 64 - elem_count_half);
tcg_gen_extract2_i64(lo, lo, hi, 64 - 2 * elem_count_half);
r~
