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tcg/riscv: Add the mov and movi instruction

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Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Michael Clark <mjc@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <bd6a45c73a67b77ddaa2fe590a6bb8ee422b9683.1545246859.git.alistair.francis@wdc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Alistair Francis 2018-12-19 19:18:17 +00:00 committed by Richard Henderson
parent dfa8e74f94
commit 6cd2eda39f
1 changed files with 86 additions and 0 deletions
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86
tcg/riscv/tcg-target.inc.c
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@ -510,3 +510,89 @@ static bool patch_reloc(tcg_insn_unit *code_ptr, int type,
tcg_abort();
}
}
/*
* TCG intrinsics
*/
static void tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg)
{
if (ret == arg) {
return;
}
switch (type) {
case TCG_TYPE_I32:
case TCG_TYPE_I64:
tcg_out_opc_imm(s, OPC_ADDI, ret, arg, 0);
break;
default:
g_assert_not_reached();
}
}
static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd,
tcg_target_long val)
{
tcg_target_long lo, hi, tmp;
int shift, ret;
if (TCG_TARGET_REG_BITS == 64 && type == TCG_TYPE_I32) {
val = (int32_t)val;
}
lo = sextreg(val, 0, 12);
if (val == lo) {
tcg_out_opc_imm(s, OPC_ADDI, rd, TCG_REG_ZERO, lo);
return;
}
hi = val - lo;
if (TCG_TARGET_REG_BITS == 32 || val == (int32_t)val) {
tcg_out_opc_upper(s, OPC_LUI, rd, hi);
if (lo != 0) {
tcg_out_opc_imm(s, OPC_ADDIW, rd, rd, lo);
}
return;
}
/* We can only be here if TCG_TARGET_REG_BITS != 32 */
tmp = tcg_pcrel_diff(s, (void *)val);
if (tmp == (int32_t)tmp) {
tcg_out_opc_upper(s, OPC_AUIPC, rd, 0);
tcg_out_opc_imm(s, OPC_ADDI, rd, rd, 0);
ret = reloc_call(s->code_ptr - 2, (tcg_insn_unit *)val);
tcg_debug_assert(ret == true);
return;
}
/* Look for a single 20-bit section. */
shift = ctz64(val);
tmp = val >> shift;
if (tmp == sextreg(tmp, 0, 20)) {
tcg_out_opc_upper(s, OPC_LUI, rd, tmp << 12);
if (shift > 12) {
tcg_out_opc_imm(s, OPC_SLLI, rd, rd, shift - 12);
} else {
tcg_out_opc_imm(s, OPC_SRAI, rd, rd, 12 - shift);
}
return;
}
/* Look for a few high zero bits, with lots of bits set in the middle. */
shift = clz64(val);
tmp = val << shift;
if (tmp == sextreg(tmp, 12, 20) << 12) {
tcg_out_opc_upper(s, OPC_LUI, rd, tmp);
tcg_out_opc_imm(s, OPC_SRLI, rd, rd, shift);
return;
} else if (tmp == sextreg(tmp, 0, 12)) {
tcg_out_opc_imm(s, OPC_ADDI, rd, TCG_REG_ZERO, tmp);
tcg_out_opc_imm(s, OPC_SRLI, rd, rd, shift);
return;
}
/* Drop into the constant pool. */
new_pool_label(s, val, R_RISCV_CALL, s->code_ptr, 0);
tcg_out_opc_upper(s, OPC_AUIPC, rd, 0);
tcg_out_opc_imm(s, OPC_LD, rd, rd, 0);
}