From: Richard Henderson Date: Tue, 16 Jan 2018 13:28:13 +0000 (+0000) Subject: target/arm: Split out vfp_expand_imm X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e90a99fe6bde9b85bff8c052ade51520f20d9bce;p=qemu.git target/arm: Split out vfp_expand_imm Signed-off-by: Richard Henderson Reviewed-by: Peter Maydell Message-id: 20180110063337.21538-2-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index ba94f7d045..80ae019172 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -4985,6 +4985,33 @@ static void disas_fp_3src(DisasContext *s, uint32_t insn) } } +/* The imm8 encodes the sign bit, enough bits to represent an exponent in + * the range 01....1xx to 10....0xx, and the most significant 4 bits of + * the mantissa; see VFPExpandImm() in the v8 ARM ARM. + */ +static uint64_t vfp_expand_imm(int size, uint8_t imm8) +{ + uint64_t imm; + + switch (size) { + case MO_64: + imm = (extract32(imm8, 7, 1) ? 0x8000 : 0) | + (extract32(imm8, 6, 1) ? 0x3fc0 : 0x4000) | + extract32(imm8, 0, 6); + imm <<= 48; + break; + case MO_32: + imm = (extract32(imm8, 7, 1) ? 0x8000 : 0) | + (extract32(imm8, 6, 1) ? 0x3e00 : 0x4000) | + (extract32(imm8, 0, 6) << 3); + imm <<= 16; + break; + default: + g_assert_not_reached(); + } + return imm; +} + /* Floating point immediate * 31 30 29 28 24 23 22 21 20 13 12 10 9 5 4 0 * +---+---+---+-----------+------+---+------------+-------+------+------+ @@ -5008,22 +5035,7 @@ static void disas_fp_imm(DisasContext *s, uint32_t insn) return; } - /* The imm8 encodes the sign bit, enough bits to represent - * an exponent in the range 01....1xx to 10....0xx, - * and the most significant 4 bits of the mantissa; see - * VFPExpandImm() in the v8 ARM ARM. - */ - if (is_double) { - imm = (extract32(imm8, 7, 1) ? 0x8000 : 0) | - (extract32(imm8, 6, 1) ? 0x3fc0 : 0x4000) | - extract32(imm8, 0, 6); - imm <<= 48; - } else { - imm = (extract32(imm8, 7, 1) ? 0x8000 : 0) | - (extract32(imm8, 6, 1) ? 0x3e00 : 0x4000) | - (extract32(imm8, 0, 6) << 3); - imm <<= 16; - } + imm = vfp_expand_imm(MO_32 + is_double, imm8); tcg_res = tcg_const_i64(imm); write_fp_dreg(s, rd, tcg_res);