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target/riscv: Check nanboxed inputs in trans_rvf.inc.c

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If a 32-bit input is not properly nanboxed, then the input is replaced
with the default qnan.  The only inline expansion is for the sign-changing
set of instructions: FSGNJ.S, FSGNJX.S, FSGNJN.S.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Message-Id: <20200724002807.441147-6-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This commit is contained in:
Richard Henderson 2020-07-23 17:28:05 -07:00 • committed by Alistair Francis
parent 00e925c560
commit ffe70e4dfc
2 changed files with 73 additions and 16 deletions
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18
target/riscv/translate.c
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@ -101,6 +101,24 @@ static void gen_nanbox_s(TCGv_i64 out, TCGv_i64 in)
tcg_gen_ori_i64(out, in, MAKE_64BIT_MASK(32, 32));
}
/*
* A narrow n-bit operation, where n < FLEN, checks that input operands
* are correctly Nan-boxed, i.e., all upper FLEN - n bits are 1.
* If so, the least-significant bits of the input are used, otherwise the
* input value is treated as an n-bit canonical NaN (v2.2 section 9.2).
*
* Here, the result is always nan-boxed, even the canonical nan.
*/
static void gen_check_nanbox_s(TCGv_i64 out, TCGv_i64 in)
{
TCGv_i64 t_max = tcg_const_i64(0xffffffff00000000ull);
TCGv_i64 t_nan = tcg_const_i64(0xffffffff7fc00000ull);
tcg_gen_movcond_i64(TCG_COND_GEU, out, in, t_max, in, t_nan);
tcg_temp_free_i64(t_max);
tcg_temp_free_i64(t_nan);
}
static void generate_exception(DisasContext *ctx, int excp)
{
tcg_gen_movi_tl(cpu_pc, ctx->base.pc_next);