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target/ppc: Optimize emulation of vclzd instruction

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Optimize Altivec instruction vclzd (Vector Count Leading Zeros Doubleword).
This instruction counts the number of leading zeros of each doubleword element
in source register and places result in the appropriate doubleword element of
destination register.

Using tcg-s count leading zeros instruction two times(once for each
doubleword element of source register vB) and placing result in
appropriate doubleword element of destination register vD.

Signed-off-by: Stefan Brankovic <stefan.brankovic@rt-rk.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1563200574-11098-6-git-send-email-stefan.brankovic@rt-rk.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Stefan Brankovic 2019-07-15 16:22:51 +02:00 committed by David Gibson
parent 083b3f012f
commit b8313f0d91
3 changed files with 27 additions and 5 deletions
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1
target/ppc/helper.h
View File

@ -311,7 +311,6 @@ DEF_HELPER_4(vctsxs, void, env, avr, avr, i32)
DEF_HELPER_2(vclzb, void, avr, avr)
DEF_HELPER_2(vclzh, void, avr, avr)
DEF_HELPER_2(vclzw, void, avr, avr)
DEF_HELPER_2(vclzd, void, avr, avr)
DEF_HELPER_2(vctzb, void, avr, avr)
DEF_HELPER_2(vctzh, void, avr, avr)
DEF_HELPER_2(vctzw, void, avr, avr)

3
target/ppc/int_helper.c
View File

@ -1820,17 +1820,14 @@ VUPK(lsw, s64, s32, UPKLO)
#define clzb(v) ((v) ? clz32((uint32_t)(v) << 24) : 8)
#define clzh(v) ((v) ? clz32((uint32_t)(v) << 16) : 16)
#define clzw(v) clz32((v))
#define clzd(v) clz64((v))
VGENERIC_DO(clzb, u8)
VGENERIC_DO(clzh, u16)
VGENERIC_DO(clzw, u32)
VGENERIC_DO(clzd, u64)
#undef clzb
#undef clzh
#undef clzw
#undef clzd
#define ctzb(v) ((v) ? ctz32(v) : 8)
#define ctzh(v) ((v) ? ctz32(v) : 16)

28
target/ppc/translate/vmx-impl.inc.c
View File

@ -742,6 +742,32 @@ static void trans_vgbbd(DisasContext *ctx)
tcg_temp_free_i64(avr[1]);
}
/*
* vclzd VRT,VRB - Vector Count Leading Zeros Doubleword
*
* Counting the number of leading zero bits of each doubleword element in source
* register and placing result in appropriate doubleword element of destination
* register.
*/
static void trans_vclzd(DisasContext *ctx)
{
int VT = rD(ctx->opcode);
int VB = rB(ctx->opcode);
TCGv_i64 avr = tcg_temp_new_i64();
/* high doubleword */
get_avr64(avr, VB, true);
tcg_gen_clzi_i64(avr, avr, 64);
set_avr64(VT, avr, true);
/* low doubleword */
get_avr64(avr, VB, false);
tcg_gen_clzi_i64(avr, avr, 64);
set_avr64(VT, avr, false);
tcg_temp_free_i64(avr);
}
GEN_VXFORM(vmuloub, 4, 0);
GEN_VXFORM(vmulouh, 4, 1);
GEN_VXFORM(vmulouw, 4, 2);
@ -1258,7 +1284,7 @@ GEN_VAFORM_PAIRED(vmaddfp, vnmsubfp, 23)
GEN_VXFORM_NOA(vclzb, 1, 28)
GEN_VXFORM_NOA(vclzh, 1, 29)
GEN_VXFORM_NOA(vclzw, 1, 30)
GEN_VXFORM_NOA(vclzd, 1, 31)
GEN_VXFORM_TRANS(vclzd, 1, 31)
GEN_VXFORM_NOA_2(vnegw, 1, 24, 6)
GEN_VXFORM_NOA_2(vnegd, 1, 24, 7)
GEN_VXFORM_NOA_2(vextsb2w, 1, 24, 16)