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tcg/i386: Support bswap flags

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Retain the current rorw bswap16 expansion for the zero-in/zero-out case.
Otherwise, perform a wider bswap plus a right-shift or extend.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2021-06-12 22:42:13 -07:00
parent 587195bd59
commit 7335a3d69f
1 changed files with 19 additions and 1 deletions
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20
tcg/i386/tcg-target.c.inc
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@ -2421,10 +2421,28 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
break;
OP_32_64(bswap16):
tcg_out_rolw_8(s, a0);
if (a2 & TCG_BSWAP_OS) {
/* Output must be sign-extended. */
if (rexw) {
tcg_out_bswap64(s, a0);
tcg_out_shifti(s, SHIFT_SAR + rexw, a0, 48);
} else {
tcg_out_bswap32(s, a0);
tcg_out_shifti(s, SHIFT_SAR, a0, 16);
}
} else if ((a2 & (TCG_BSWAP_IZ | TCG_BSWAP_OZ)) == TCG_BSWAP_OZ) {
/* Output must be zero-extended, but input isn't. */
tcg_out_bswap32(s, a0);
tcg_out_shifti(s, SHIFT_SHR, a0, 16);
} else {
tcg_out_rolw_8(s, a0);
}
break;
OP_32_64(bswap32):
tcg_out_bswap32(s, a0);
if (rexw && (a2 & TCG_BSWAP_OS)) {
tcg_out_ext32s(s, a0, a0);
}
break;
OP_32_64(neg):