From e9bffec9afc45cf7c49308f0b4b8cc6bf68f58f2 Mon Sep 17 00:00:00 2001 From: "Jose E. Marchesi" Date: Thu, 4 Jun 2020 16:15:53 +0200 Subject: opcodes: discriminate endianness and insn-endianness in CGEN ports The CGEN support code in opcodes accesses instruction contents using a couple of functions defined in cgen-opc.c: cgen_get_insn_value and cgen_put_insn_value. These functions use the "instruction endianness" in the CPU description to order the read/written bytes. The process of writing an instruction to the object file is: a) cgen_put_insn_value ;; Writes out the opcodes. b) ARCH_cgen_insert_operand insert_normal insert_1 cgen_put_insn_value ;; Writes out the bytes of the ;; operand. Likewise, the process of reading an instruction from the object file is: a) cgen_get_insn_value ;; Reads the opcodes. b) ARCH_cgen_extract_operand extract_normal extract_1 cgen_get_insn_value ;; Reads in the bytes of the ;; operand. As can be seen above, cgen_{get,put}_insn_value are used to both process the instruction opcodes (the constant fields conforming the base instruction) and also the values of the instruction operands, such as immediates. This is problematic for architectures in which the endianness of instructions is different to the endianness of data. An example is BPF, where instructions are always encoded big-endian but the data may be either big or little. This patch changes the cgen_{get,put}_insn_value functions in order to get an extra argument with the endianness to use, and adapts the existin callers to these functions in order to provide cd->endian or cd->insn_endian, whatever appropriate. Callers like extract_1 and insert_1 pass cd->endian (since they are reading/writing operand values) while callers reading/writing the base instruction pass cd->insn_endian instead. A few little adjustments have been needed in some existing CGEN based ports: * The BPF assembler uses cgen_put_insn_value. It has been adapted to pass the new endian argument. * The mep port has code in mep.opc that uses cgen_{get,put}_insn_value. It has been adapted to pass the new endianargument. Ditto for a call in the assembler. Tested with --enable-targets=all. Regested in all supported targets. No regressions. include/ChangeLog: 2020-06-04 Jose E. Marchesi * opcode/cgen.h: Get an `endian' argument in both cgen_get_insn_value and cgen_put_insn_value. opcodes/ChangeLog: 2020-06-04 Jose E. Marchesi * cgen-opc.c (cgen_get_insn_value): Get an `endian' argument. (cgen_put_insn_value): Likewise. (cgen_lookup_insn): Pass endianness to cgen_{get,put}_insn_value. * cgen-dis.in (print_insn): Likewise. * cgen-ibld.in (insert_1): Likewise. (insert_1): Likewise. (insert_insn_normal): Likewise. (extract_1): Likewise. * bpf-dis.c: Regenerate. * bpf-ibld.c: Likewise. * bpf-ibld.c: Likewise. * cgen-dis.in: Likewise. * cgen-ibld.in: Likewise. * cgen-opc.c: Likewise. * epiphany-dis.c: Likewise. * epiphany-ibld.c: Likewise. * fr30-dis.c: Likewise. * fr30-ibld.c: Likewise. * frv-dis.c: Likewise. * frv-ibld.c: Likewise. * ip2k-dis.c: Likewise. * ip2k-ibld.c: Likewise. * iq2000-dis.c: Likewise. * iq2000-ibld.c: Likewise. * lm32-dis.c: Likewise. * lm32-ibld.c: Likewise. * m32c-dis.c: Likewise. * m32c-ibld.c: Likewise. * m32r-dis.c: Likewise. * m32r-ibld.c: Likewise. * mep-dis.c: Likewise. * mep-ibld.c: Likewise. * mt-dis.c: Likewise. * mt-ibld.c: Likewise. * or1k-dis.c: Likewise. * or1k-ibld.c: Likewise. * xc16x-dis.c: Likewise. * xc16x-ibld.c: Likewise. * xstormy16-dis.c: Likewise. * xstormy16-ibld.c: Likewise. gas/ChangeLog: 2020-06-04 Jose E. Marchesi * cgen.c (gas_cgen_finish_insn): Pass the endianness to cgen_put_insn_value. (gas_cgen_md_apply_fix): Likewise. (gas_cgen_md_apply_fix): Likewise. * config/tc-bpf.c (md_apply_fix): Pass data endianness to cgen_put_insn_value. * config/tc-mep.c (mep_check_ivc2_scheduling): Pass endianness to cgen_put_insn_value. cpu/ChangeLog: 2020-06-02 Jose E. Marchesi * mep.opc (print_slot_insn): Pass the insn endianness to cgen_get_insn_value. --- gas/cgen.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'gas/cgen.c') diff --git a/gas/cgen.c b/gas/cgen.c index b94802e..8d1867b 100644 --- a/gas/cgen.c +++ b/gas/cgen.c @@ -621,7 +621,8 @@ gas_cgen_finish_insn (const CGEN_INSN *insn, CGEN_INSN_BYTES_PTR buf, /* If we're recording insns as numbers (rather than a string of bytes), target byte order handling is deferred until now. */ #if CGEN_INT_INSN_P - cgen_put_insn_value (gas_cgen_cpu_desc, (unsigned char *) f, length, *buf); + cgen_put_insn_value (gas_cgen_cpu_desc, (unsigned char *) f, length, *buf, + gas_cgen_cpu_desc->insn_endian); #else memcpy (f, buf, byte_len); #endif @@ -906,13 +907,15 @@ gas_cgen_md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED) { CGEN_INSN_INT insn_value = cgen_get_insn_value (cd, (unsigned char *) where, - CGEN_INSN_BITSIZE (insn)); + CGEN_INSN_BITSIZE (insn), + cd->insn_endian); /* ??? 0 is passed for `pc'. */ errmsg = CGEN_CPU_INSERT_OPERAND (cd) (cd, opindex, fields, &insn_value, (bfd_vma) 0); cgen_put_insn_value (cd, (unsigned char *) where, - CGEN_INSN_BITSIZE (insn), insn_value); + CGEN_INSN_BITSIZE (insn), insn_value, + cd->insn_endian); } #else /* ??? 0 is passed for `pc'. */ -- cgit v1.1