dt_cg.c

Sun Solaris 10 中的 DTrace 组件的源代码。请参看: http://www.sun.com/software/solaris/observability.jsp

		dt_cg_compare_op(dnp, dlp, drp,
		    dt_cg_compare_signed(dnp) ? DIF_OP_BL : DIF_OP_BLU);
		break;

	case DT_TOK_LE:
		dt_cg_compare_op(dnp, dlp, drp,
		    dt_cg_compare_signed(dnp) ? DIF_OP_BLE : DIF_OP_BLEU);
		break;

	case DT_TOK_GT:
		dt_cg_compare_op(dnp, dlp, drp,
		    dt_cg_compare_signed(dnp) ? DIF_OP_BG : DIF_OP_BGU);
		break;

	case DT_TOK_GE:
		dt_cg_compare_op(dnp, dlp, drp,
		    dt_cg_compare_signed(dnp) ? DIF_OP_BGE : DIF_OP_BGEU);
		break;

	case DT_TOK_LSH:
		dt_cg_arithmetic_op(dnp, dlp, drp, DIF_OP_SLL);
		break;

	case DT_TOK_RSH:
		dt_cg_arithmetic_op(dnp, dlp, drp,
		    (dnp->dn_flags & DT_NF_SIGNED) ? DIF_OP_SRA : DIF_OP_SRL);
		break;

	case DT_TOK_ADD:
		dt_cg_arithmetic_op(dnp, dlp, drp, DIF_OP_ADD);
		break;

	case DT_TOK_SUB:
		dt_cg_arithmetic_op(dnp, dlp, drp, DIF_OP_SUB);
		break;

	case DT_TOK_MUL:
		dt_cg_arithmetic_op(dnp, dlp, drp, DIF_OP_MUL);
		break;

	case DT_TOK_DIV:
		dt_cg_arithmetic_op(dnp, dlp, drp,
		    (dnp->dn_flags & DT_NF_SIGNED) ? DIF_OP_SDIV : DIF_OP_UDIV);
		break;

	case DT_TOK_MOD:
		dt_cg_arithmetic_op(dnp, dlp, drp,
		    (dnp->dn_flags & DT_NF_SIGNED) ? DIF_OP_SREM : DIF_OP_UREM);
		break;

	case DT_TOK_LNEG:
		dt_cg_logical_neg(dnp, dlp, drp);
		break;

	case DT_TOK_BNEG:
		dt_cg_node(dnp->dn_child, dlp, drp);
		dnp->dn_reg = dnp->dn_child->dn_reg;
		instr = DIF_INSTR_NOT(dnp->dn_reg, dnp->dn_reg);
		dt_irlist_append(dlp, dt_cg_node_alloc(DT_LBL_NONE, instr));
		break;

	case DT_TOK_PREINC:
		dt_cg_prearith_op(dnp, dlp, drp, DIF_OP_ADD);
		break;

	case DT_TOK_POSTINC:
		dt_cg_postarith_op(dnp, dlp, drp, DIF_OP_ADD);
		break;

	case DT_TOK_PREDEC:
		dt_cg_prearith_op(dnp, dlp, drp, DIF_OP_SUB);
		break;

	case DT_TOK_POSTDEC:
		dt_cg_postarith_op(dnp, dlp, drp, DIF_OP_SUB);
		break;

	case DT_TOK_IPOS:
		dt_cg_node(dnp->dn_child, dlp, drp);
		dnp->dn_reg = dnp->dn_child->dn_reg;
		break;

	case DT_TOK_INEG:
		dt_cg_node(dnp->dn_child, dlp, drp);
		dnp->dn_reg = dnp->dn_child->dn_reg;

		instr = DIF_INSTR_FMT(DIF_OP_SUB, DIF_REG_R0,
		    dnp->dn_reg, dnp->dn_reg);

		dt_irlist_append(dlp, dt_cg_node_alloc(DT_LBL_NONE, instr));
		break;

	case DT_TOK_DEREF:
		dt_cg_node(dnp->dn_child, dlp, drp);
		dnp->dn_reg = dnp->dn_child->dn_reg;

		if (!(dnp->dn_flags & DT_NF_REF)) {
			uint_t ubit = dnp->dn_flags & DT_NF_USERLAND;

			/*
			 * Save and restore DT_NF_USERLAND across dt_cg_load():
			 * we need the sign bit from dnp and the user bit from
			 * dnp->dn_child in order to get the proper opcode.
			 */
			dnp->dn_flags |=
			    (dnp->dn_child->dn_flags & DT_NF_USERLAND);

			instr = DIF_INSTR_LOAD(dt_cg_load(dnp, ctfp,
			    dnp->dn_type), dnp->dn_reg, dnp->dn_reg);

			dnp->dn_flags &= ~DT_NF_USERLAND;
			dnp->dn_flags |= ubit;

			dt_irlist_append(dlp,
			    dt_cg_node_alloc(DT_LBL_NONE, instr));
		}
		break;

	case DT_TOK_ADDROF: {
		uint_t rbit = dnp->dn_child->dn_flags & DT_NF_REF;

		dnp->dn_child->dn_flags |= DT_NF_REF; /* force pass-by-ref */
		dt_cg_node(dnp->dn_child, dlp, drp);
		dnp->dn_reg = dnp->dn_child->dn_reg;

		dnp->dn_child->dn_flags &= ~DT_NF_REF;
		dnp->dn_child->dn_flags |= rbit;
		break;
	}

	case DT_TOK_SIZEOF: {
		size_t size = dt_node_sizeof(dnp->dn_child);

		if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
			longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

		assert(size != 0);
		dt_cg_setx(dlp, dnp->dn_reg, size);
		break;
	}

	case DT_TOK_STRINGOF:
		dt_cg_node(dnp->dn_child, dlp, drp);
		dnp->dn_reg = dnp->dn_child->dn_reg;
		break;

	case DT_TOK_XLATE:
		dt_cg_node(dnp->dn_right, dlp, drp);
		dnp->dn_reg = dnp->dn_right->dn_reg;
		break;

	case DT_TOK_LPAR:
		dt_cg_node(dnp->dn_right, dlp, drp);
		dnp->dn_reg = dnp->dn_right->dn_reg;
		dt_cg_typecast(dnp->dn_right, dnp, dlp, drp);
		break;

	case DT_TOK_PTR:
	case DT_TOK_DOT:
		assert(dnp->dn_right->dn_kind == DT_NODE_IDENT);
		dt_cg_node(dnp->dn_left, dlp, drp);

		/*
		 * If the left-hand side of PTR or DOT is a dynamic variable,
		 * we expect it to be the output of a D translator.   In this
		 * case, we look up the parse tree corresponding to the member
		 * that is being accessed and run the code generator over it.
		 * We then cast the result as if by the assignment operator.
		 */
		if (dt_node_is_dynamic(dnp->dn_left)) {
			dt_ident_t *idp;
			dt_xlator_t *dxp;
			dt_node_t *mnp;

			idp = dt_ident_resolve(dnp->dn_left->dn_ident);
			assert(idp->di_kind == DT_IDENT_XLSOU ||
			    idp->di_kind == DT_IDENT_XLPTR);
			dxp = idp->di_data;

			mnp = dt_xlator_member(dxp, dnp->dn_right->dn_string);
			assert(mnp != NULL);

			dxp->dx_ident->di_flags |= DT_IDFLG_CGREG;
			dxp->dx_ident->di_id = dnp->dn_left->dn_reg;

			dt_cg_node(mnp->dn_membexpr, dlp, drp);
			dnp->dn_reg = mnp->dn_membexpr->dn_reg;
			dt_cg_typecast(mnp->dn_membexpr, dnp, dlp, drp);

			dxp->dx_ident->di_flags &= ~DT_IDFLG_CGREG;
			dxp->dx_ident->di_id = 0;

			dt_regset_free(drp, dnp->dn_left->dn_reg);
			break;
		}

		ctfp = dnp->dn_left->dn_ctfp;
		type = ctf_type_resolve(ctfp, dnp->dn_left->dn_type);

		if (dnp->dn_op == DT_TOK_PTR) {
			type = ctf_type_reference(ctfp, type);
			type = ctf_type_resolve(ctfp, type);
		}

		if ((ctfp = dt_cg_membinfo(octfp = ctfp, type,
		    dnp->dn_right->dn_string, &m)) == NULL) {
			yypcb->pcb_hdl->dt_ctferr = ctf_errno(octfp);
			longjmp(yypcb->pcb_jmpbuf, EDT_CTF);
		}

		if (m.ctm_offset != 0) {
			if ((reg = dt_regset_alloc(drp)) == -1)
				longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

			/*
			 * If the offset is not aligned on a byte boundary, it
			 * is a bit-field member and we will extract the value
			 * bits below after we generate the appropriate load.
			 */
			dt_cg_setx(dlp, reg, m.ctm_offset / NBBY);

			instr = DIF_INSTR_FMT(DIF_OP_ADD,
			    dnp->dn_left->dn_reg, reg, dnp->dn_left->dn_reg);

			dt_irlist_append(dlp,
			    dt_cg_node_alloc(DT_LBL_NONE, instr));
			dt_regset_free(drp, reg);
		}

		if (!(dnp->dn_flags & DT_NF_REF)) {
			uint_t ubit = dnp->dn_flags & DT_NF_USERLAND;

			/*
			 * Save and restore DT_NF_USERLAND across dt_cg_load():
			 * we need the sign bit from dnp and the user bit from
			 * dnp->dn_left in order to get the proper opcode.
			 */
			dnp->dn_flags |=
			    (dnp->dn_left->dn_flags & DT_NF_USERLAND);

			instr = DIF_INSTR_LOAD(dt_cg_load(dnp,
			    ctfp, m.ctm_type), dnp->dn_left->dn_reg,
			    dnp->dn_left->dn_reg);

			dnp->dn_flags &= ~DT_NF_USERLAND;
			dnp->dn_flags |= ubit;

			dt_irlist_append(dlp,
			    dt_cg_node_alloc(DT_LBL_NONE, instr));

			if (dnp->dn_flags & DT_NF_BITFIELD)
				dt_cg_field_get(dnp, dlp, drp, ctfp, &m);
		}

		dnp->dn_reg = dnp->dn_left->dn_reg;
		break;

	case DT_TOK_STRING:
		if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
			longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

		assert(dnp->dn_kind == DT_NODE_STRING);
		stroff = dt_strtab_insert(yypcb->pcb_strtab, dnp->dn_string);

		if (stroff == -1L)
			longjmp(yypcb->pcb_jmpbuf, EDT_NOMEM);
		if (stroff > DIF_STROFF_MAX)
			longjmp(yypcb->pcb_jmpbuf, EDT_STR2BIG);

		instr = DIF_INSTR_SETS((ulong_t)stroff, dnp->dn_reg);
		dt_irlist_append(dlp, dt_cg_node_alloc(DT_LBL_NONE, instr));
		break;

	case DT_TOK_IDENT:
		/*
		 * If the specified identifier is a variable on which we have
		 * set the code generator register flag, then this variable
		 * has already had code generated for it and saved in di_id.
		 * Allocate a new register and copy the existing value to it.
		 */
		if (dnp->dn_kind == DT_NODE_VAR &&
		    (dnp->dn_ident->di_flags & DT_IDFLG_CGREG)) {
			if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
				longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);
			instr = DIF_INSTR_MOV(dnp->dn_ident->di_id,
			    dnp->dn_reg);
			dt_irlist_append(dlp,
			    dt_cg_node_alloc(DT_LBL_NONE, instr));
			break;
		}

		/*
		 * Identifiers can represent function calls, variable refs, or
		 * symbols.  First we check for inlined variables, and handle
		 * them by generating code for the inline parse tree, and then
		 * casting the result to the inline's output type.
		 */
		if (dnp->dn_kind == DT_NODE_VAR &&
		    (dnp->dn_ident->di_flags & DT_IDFLG_INLINE)) {
			dt_idnode_t *inp = dnp->dn_ident->di_data;

			dt_cg_node(inp->din_root, dlp, drp);
			dnp->dn_reg = inp->din_root->dn_reg;
			dt_cg_typecast(inp->din_root, dnp, dlp, drp);

			break;
		}

		switch (dnp->dn_kind) {
		case DT_NODE_FUNC: {
			dt_ident_t *idp = dnp->dn_ident;

			if (idp->di_kind != DT_IDENT_FUNC) {
				yylineno = dnp->dn_line;
				xyerror(D_CG_EXPR, "%s %s( ) may not be "
				    "called from a D expression (D program "
				    "context required)\n",
				    dt_idkind_name(idp->di_kind), idp->di_name);
			}

			dt_cg_arglist(dnp->dn_ident, dnp->dn_args, dlp, drp);

			if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
				longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

			instr = DIF_INSTR_CALL(
			    dnp->dn_ident->di_id, dnp->dn_reg);

			dt_irlist_append(dlp,
			    dt_cg_node_alloc(DT_LBL_NONE, instr));

			break;
		}

		case DT_NODE_VAR:
			if (dnp->dn_ident->di_kind == DT_IDENT_XLSOU ||
			    dnp->dn_ident->di_kind == DT_IDENT_XLPTR) {
				/*
				 * This can only happen if we have translated
				 * args[].
				 */
				assert(dnp->dn_ident->di_id == DIF_VAR_ARGS);
				dt_cg_array_op(dnp, dlp, drp);
				break;
			}

			if (dnp->dn_ident->di_kind == DT_IDENT_ARRAY) {
				if (dnp->dn_ident->di_id > DIF_VAR_ARRAY_MAX)
					dt_cg_assoc_op(dnp, dlp, drp);
				else
					dt_cg_array_op(dnp, dlp, drp);
				break;
			}

			if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
				longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

			if (dnp->dn_ident->di_flags & DT_IDFLG_LOCAL)
				op = DIF_OP_LDLS;
			else if (dnp->dn_ident->di_flags & DT_IDFLG_TLS)
				op = DIF_OP_LDTS;
			else
				op = DIF_OP_LDGS;

			dnp->dn_ident->di_flags |= DT_IDFLG_DIFR;

			instr = DIF_INSTR_LDV(op,
			    dnp->dn_ident->di_id, dnp->dn_reg);

			dt_irlist_append(dlp,
			    dt_cg_node_alloc(DT_LBL_NONE, instr));
			break;

		case DT_NODE_SYM: {
			dtrace_hdl_t *dtp = yypcb->pcb_hdl;
			dtrace_syminfo_t *sip = dnp->dn_ident->di_data;
			GElf_Sym sym;

			if (dtrace_lookup_by_name(dtp,
			    sip->dts_object, sip->dts_name, &sym, NULL) == -1) {
				xyerror(D_UNKNOWN, "cg failed for symbol %s`%s:"
				    " %s\n", sip->dts_object, sip->dts_name,
				    dtrace_errmsg(dtp, dtrace_errno(dtp)));
			}

			if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
				longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

			dt_cg_xsetx(dlp, dnp->dn_ident,
			    DT_LBL_NONE, dnp->dn_reg, sym.st_value);

			if (!(dnp->dn_flags & DT_NF_REF)) {
				instr = DIF_INSTR_LOAD(dt_cg_load(dnp, ctfp,
				    dnp->dn_type), dnp->dn_reg, dnp->dn_reg);
				dt_irlist_append(dlp,
				    dt_cg_node_alloc(DT_LBL_NONE, instr));
			}
			break;
		}

		default:
			xyerror(D_UNKNOWN, "internal error -- node type %u is "
			    "not valid for an identifier\n", dnp->dn_kind);
		}
		break;

	case DT_TOK_INT:
		if ((dnp->dn_reg = dt_regset_alloc(drp)) == -1)
			longjmp(yypcb->pcb_jmpbuf, EDT_NOREG);

		dt_cg_setx(dlp, dnp->dn_reg, dnp->dn_value);
		break;

	default:
		xyerror(D_UNKNOWN, "internal error -- token type %u is not a "
		    "valid D compilation token\n", dnp->dn_op);
	}
}

void
dt_cg(dt_pcb_t *pcb, dt_node_t *dnp)
{
	dif_instr_t instr;

	if (pcb->pcb_regs == NULL && (pcb->pcb_regs =
	    dt_regset_create(pcb->pcb_hdl->dt_conf.dtc_difintregs)) == NULL)
		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);

	dt_regset_reset(pcb->pcb_regs);
	(void) dt_regset_alloc(pcb->pcb_regs); /* allocate %r0 */

	if (pcb->pcb_inttab != NULL)
		dt_inttab_destroy(pcb->pcb_inttab);

	if ((pcb->pcb_inttab = dt_inttab_create(yypcb->pcb_hdl)) == NULL)
		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);

	if (pcb->pcb_strtab != NULL)
		dt_strtab_destroy(pcb->pcb_strtab);

	if ((pcb->pcb_strtab = dt_strtab_create(BUFSIZ)) == NULL)
		longjmp(pcb->pcb_jmpbuf, EDT_NOMEM);

	dt_irlist_destroy(&pcb->pcb_ir);
	dt_irlist_create(&pcb->pcb_ir);

	assert(pcb->pcb_dret == NULL);
	pcb->pcb_dret = dnp;

	if (dt_node_is_dynamic(dnp)) {
		dnerror(dnp, D_CG_DYN, "expression cannot evaluate to result "
		    "of dynamic type\n");
	}

	dt_cg_node(dnp, &pcb->pcb_ir, pcb->pcb_regs);
	instr = DIF_INSTR_RET(dnp->dn_reg);
	dt_regset_free(pcb->pcb_regs, dnp->dn_reg);
	dt_irlist_append(&pcb->pcb_ir, dt_cg_node_alloc(DT_LBL_NONE, instr));
}