IRIX Base Documentation 2002 November

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- 1 - 7.3 Fortran 90 Release Notes - 2 - 4. _N_e_w__F_e_a_t_u_r_e_s This chapter lists the MIPSpro 7 Fortran 90 features for the 7.3 release, including the new Fortran 95 features. The MIPSpro 7 Fortran 90 compiler now fully supports Fortran 95. 4.1 _N_e_w__C_o_m_p_i_l_e_r__C_o_m_m_a_n_d__L_i_n_e__O_p_t_i_o_n_s The following sections describe the new f90 command line options supported with the MIPSpro 7.3 release. 4.1.1 _C_h_e_c_k_s__a_n_d__C_o_m_m_e_n_t_s The -fullwarn option requests that the compiler perform additional checks and generate comment- level messages. These messages are suppressed by default. Specifying this option can be useful during software development. 4.1.2 _C_o_d_e__S_c_h_e_d_u_l_e_r The -r12000 option specifies the code scheduler for the R12000(TM) processor. 4.1.3 _S_t_a_t_i_c__V_a_r_i_a_b_l_e_s The -static_thread_private option makes all static variables private to each thread. This option can be combined with the -static option that promotes local/automatic variables to be static. 4.1.4 _C_o_n_f_o_r_m_a_n_c_e__C_h_e_c_k_i_n_g The DEBUG:conform_check option determines whether conformance checking is enabled. When set to YES, the compiler generates code to check if operands are conformable. Conformance check failures generate run-time warnings unless the environment variable F90_CONFORM_CHECK_ABORT is set to YES. The default is OFF. - 3 - 4.1.5 _E_x_t_e_r_n_a_l__N_a_m_e_s The -noappend option for external names is now supported. This option prevents the compiler from appending a trailing underbar on external names. 4.1.6 _F_e_e_d_b_a_c_k__F_i_l_e__S_p_e_c_i_f_i_c_a_t_i_o_n The -fb<_f_i_l_e> option specifies a feedback file for use with the prof(1) command. 4.1.7 _I_n_t_e_r_p_r_o_c_e_d_u_r_a_l__A_n_a_l_y_z_e_r__O_p_t_i_o_n__G_r_o_u_p New flags for the -IPA option group are as follows: common_pad_size=_n Specifies the amount by which to pad common block array dimensions. multi_clone=_n Specifies the maximum number of clones that can be created from a single procedure. node_bloat=_n When used in conjunction with -IPA:multi_clone, specifies the maximum percentage growth of the total number of procedures relative to the original program. 4.1.8 _I_n_t_e_r_p_r_o_c_e_d_u_r_a_l__P_a_r_a_l_l_e_l_i_z_a_t_i_o_n The -ipa option invokes the Interprocedural Analyzer option group. This is a new alias for -IPA:=ON. Compiling with the -ipa and -pfa options together instructs the compiler to perform interprocedural parallelization. The compiler applies a sophisticated analysis to determine when it can parallelize loops with calls. - 4 - 4.1.9 _L_i_s_t_i_n_g__C_o_n_t_r_o_l The -flist option invokes the Fortran listing control group. This is equivalent to -FLIST:=ON. The emit_omp=_f_l_a_g suboption to the -FLIST option directs the compiler to use OpenMP(TM) directives (_f_l_a_g=ON) or MIPS(TM) multiprocessing directives (_f_l_a_g=OFF). 4.1.10 _L_o_c_a_l__A_r_r_a_y__D_i_m_e_n_s_i_o_n__P_a_d_d_i_n_g The -LNO:local_pad_size=_n option specifies the amount by which to pad local array dimensions. 4.1.11 _P_a_r_a_l_l_e_l_i_z_a_t_i_o_n__A_n_a_l_y_s_i_s The -LNO:pure={_f_l_a_g} option tells the compiler how to use the PURE attribute when gathering information about calls for parallelization analysis. The PURE attribute and the !DIR$ NOSIDE EFFECTS directive have the same meaning. The values for the flag is as follows: 0 Ignores the fact that a PURE procedure or a procedure declared with a !DIR$ NO SIDE EFFECTS directive does not modify global data or its arguments. 1 (default) Accounts for the fact that PURE procedures and !DIR$ NO SIDE EFFECT procedures do not modify global data or procedure arguments. 2 User asserts that PURE and !DIR$ NO SIDE EFFECT functions not only do not modify global data or dummy arguments of the procedure, but also do not access global data. The only nonlocal data referenced by the routine are the dummy arguments to the procedure. This is an extension of the normal meaning of PURE and !DIR$ NO SIDE EFFECTS. More agressive parallelization may occur if procedures are known not to access global data. - 5 - Fortran language multiprocessor programs are now supported by ProDev ProMP graphical user interface. (ProDev ProMP was formerly known as WorkShop Pro MPF.) Among other things, ProDev ProMP lets you see the transformed source alongside the original program source code. 4.1.12 _P_r_o_c_e_d_u_r_e__R_e_o_r_d_e_r_i_n_g The -OPT:procedure_reorder=_f_e_e_d_b_a_c_k__f_i_l_e option has been added to the ld(1) man page to specify a file for procedure ordering. The procedure_reorder option has been added to the opt(5) man page to specify whether a reorder file exists. In addition, new procedure ordering informational messages are issued. 4.1.13 _S_p_e_c_u_l_a_t_i_v_e__L_o_c_a_t_i_o_n_s The -OPT:speculative_ptr_deref={ON/OFF} option allows speculative loads of memory locations that differ by a small offset from some referenced memory location. For more information, see the opt(5) man page. 4.1.14 _T_a_r_g_e_t__O_p_t_i_o_n__G_r_o_u_p__C_o_n_t_r_o_l_s The target option group has the following new controls: dismiss_mem_faults=_f_l_a_g Forces the kernel to dismiss memory faults that occur during execution. exc_max=_v_a_l_u_e Specifies the maximum set of IEEE-754 floating point exceptions for which traps can be enabled at run time. exc_min=_v_a_l_u_e Specifies the minimum set of IEEE-754 floating point - 6 - exceptions for which traps must be enabled at run time. isa=_v_a_l_u_e Identifies the target instruction set architecture for compilation. sync=_f_l_a_g Enables or disables the use of SYNC instructions. 4.1.15 _-_T_E_N_V__S_u_b_o_p_t_i_o_n The large_got=ON/OFF suboption to the -TENV compiler option replaces the -avoid_gp_overflow and the -xgot options. 4.2 _N_e_w__O_p_t_i_o_n_s__f_o_r__t_h_e__a_s_s_i_g_n__C_o_m_m_a_n_d The following sections describe new options for the assign command. 4.2.1 _F_F_I_O__L_a_y_e_r_s The assign command now accepts the -F global option for global layers, the -F tmf option for tape layers, and the -F vms option for VAX(TM)/VMS files. 4.2.2 _D_a_t_a__C_o_n_v_e_r_s_i_o_n The following data conversion options are now available on the assign command: +o -N ieee_64 +o -N ieee_le +o -N vax - 7 - 4.3 _I_n_t_r_i_n_s_i_c_s The following sections describe intrinsics supported in the MIPSpro 7.3 release. 4.3.1 _C_E_I_L_I_N_G__a_n_d__F_L_O_O_R__I_n_t_r_i_n_s_i_c_s__E_n_h_a_n_c_e_m_e_n_t_s A second argument has been added to the CEILING and the FLOOR intrinsics. This argument is optional, and specifies the kind type of the result of the intrinsic. 4.3.2 _C_P_U___T_I_M_E__I_n_t_r_i_n_s_i_c The CPU_TIME intrinsic returns processor (user) time. It does not return system time. The following example illustrates the use of the CPU_TIME intrinsic: CALL CPU_TIME(REAL_TIME_VALUE) 4.3.3 _N_U_L_L_(_)__I_n_t_r_i_n_s_i_c The NULL() intrinsic returns a disassociated pointer. 4.4 _U_t_i_l_i_t_i_e_s__a_n_d__O_t_h_e_r__R_o_u_t_i_n_e_s The following sections describe utilities and other routines supported in the MIPSpro 7.3 release. 4.4.1 _D_a_t_a__C_o_p_y_i_n_g__U_t_i_l_i_t_y The fdcp(1) command is now available. 4.4.2 _F_o_r_t_r_a_n_-_C_a_l_l_a_b_l_e__R_o_u_t_i_n_e_s Fortran-callable versions of POPCNT, POPPAR, LEADZ, and MASK are now available. - 8 - 4.4.3 _F_o_r_t_r_a_n__P_X_F__R_o_u_t_i_n_e_s The following Fortran PXF interface routines are now available, although not yet documented: PXFAINTGET PXFAINTSET PXFCLOSE PXFDUP PXFDUP2 PXFEINTGET PXFEINTSET PXFGETISPEED PXFGETOSPEED PXFLSEEK PXFMKFIFO PXFSETISPEED PXFSETOSPEED PXFTCFLOW PXFTCFLUSH PXFTCGETATTR PXFTCGETPGRP PXFTCSENDBREAK PXFTCSETATTR PXFTCSETATTR PXFTCSETPGRP PXFSYSTEM PXFWRITE 4.4.4 _R_a_n_d_o_m__N_u_m_b_e_r__R_o_u_t_i_n_e_s The random number routines, RANF, RANSET, and RANGET have been enhanced. These changes cause slight differences in the sixteenth digit for 64-bit random numbers and from the sixteenth digit to the end of 128-bit random numbers. 4.4.5 _U_s_e_r_-_C_a_l_l_a_b_l_e__C_o_n_v_e_r_s_i_o_n__R_o_u_t_i_n_e_s The following user-callable conversion routines are now available: MIPS2IEG and IEG2MIPS Conversion between IEEE Fortran data types and IRIX IEEE Fortran data - 9 - types. MIPS2VAX and VAX2MIPS Conversion between VAX Fortran data types and IRIX IEEE Fortran data types. 4.5 _O_t_h_e_r__F_o_r_t_r_a_n__E_n_h_a_n_c_e_m_e_n_t_s The following sections describe other Fortran enhancements supported by this MIPSpro 7 Fortran 90 release. 4.5.1 _E_d_i_t__D_e_s_c_r_i_p_t_o_r__C_h_a_n_g_e_s The following edit descriptor features are now supported: +o The backslash (\) is now recognized as another carriage control indicator, as a synonym for the dollar sign ($). +o The Q edit descriptor now returns the number of characters left in a formatted record. +o An empty or zero field width is now a legal value in data edit descriptors such as I, B, O, Z, D, E, F, G, and L. This feature includes some MIPS FORTRAN 77 extensions that came from VAX Fortran. These are now pseudo standards. 4.5.2 _E_L_S_P_E_C__E_n_h_a_n_c_e_m_e_n_t_s When information regarding data that needs to be loaded relative to the Global Pointer (the gprel area) is missing from the ELSPEC file, the system generates the following messages: ld32: FATAL 173: No gprel area specified in elspec file. Try using "default_gprel" after the data section declaration. See ELSPEC(5) ld32: INFO 152: Output file removed because of error. - 10 - To correct the file, you can add the following line: default_gprel 4.5.3 _F_O_R_A_L_L__C_o_n_s_t_r_u_c_t__S_u_p_p_o_r_t Support has been added for the Fortran 95 FORALL construct. FORALL constructs and statements control the execution of assignment and pointer assignment statements with selection by sets of index values and an optional mask expression. The following example illustrates the use of the FORALL construct: integer a(10,10), b(20) forall (i = 1:m:n, k =1:mm:nn, b(i+k) > 0) a(i,k) = 1 / b(i+k) endforall Semantics are as follows: 1. Calculate the range of indices and masks. 2. Evaluate all RH expressions. 3. Do all LH assignments. The FORALL construct cannot be used with OpenMP directives. 4.5.4 _F_O_R_M_=_S_Y_S_T_E_M__S_u_p_p_o_r_t Support has been added for FORM="SYSTEM" in OPEN and INQUIRE statements. 4.5.5 _f_t_p_p _R_e_p_l_a_c_e_d _w_i_t_h _I_n_t_e_g_r_a_t_e_d _P_r_e_p_r_o_c_e_s_s_o_r ftpp has been removed from the release package and replaced with the integrated preprocessor. - 11 - 4.5.6 _G_e_n_e_r_i_c__N_a_m_e__o_n__E_N_D__I_N_T_E_R_F_A_C_E A generic name can now be specified on the END INTERFACE statement as well as on the INTERFACE statement. The name on the INTERFACE and END INTERFACE statements must be the same. 4.5.7 _G_l_o_b_a_l__S_e_m_a_n_t_i_c_s The compiler does a limited amount of semantic checking across program units within a file. For example, if you define a subroutine in the file being compiled and then call that subroutine in the same compilation, the compiler will do call site checking. 4.5.8 _I_n_i_t_i_a_l_i_z_a_t_i_o_n__o_f__D_e_r_i_v_e_d__C_o_m_p_o_n_e_n_t_s Default initialization can now be declared for each component in a derived type definition. All objects declared to be of a particular derived type have their components initialized to the values specified in the derived type definition. You can override default initialization by explicitly initializing an object declared of that type. The following example illustrates the use of default initialization of derived type components: type x integer :: i = 10 endtype type (x) :: var1 type (x) :: var2 = x(11) The value of var1%i is 10. The value of var2%i is 11. 4.5.9 _N_A_M_E_L_I_S_T _a_n_d _L_i_s_t-_D_i_r_e_c_t_e_d _I/_O _E_n_h_a_n_c_e_m_e_n_t_s Comments that begin with an exclamation point (!) are now recognized in NAMELIST input records. For more information, see the assign - 12 - command (-Y on/off option). New options (-y, -S, -W, and -U) on the assign command control the NAMELIST and list-directed output statements. 4.5.10 _N_e_g_a_t_i_v_e__F_l_o_a_t_i_n_g__P_o_i_n_t__Z_e_r_o A negative floating point zero (-0.0) is now recognized for IEEE floating point systems. The minus sign is suppressed. 4.5.11 _N_e_s_t_e_d__W_H_E_R_E__C_o_n_s_t_r_u_c_t__S_u_p_p_o_r_t WHERE constructs can now be named and contain FORALL constructs and other WHERE constructs. In addition, the ELSEWHERE statement can now contain a mask. The result is that some nested IF constructs can be translated to array notation without forming complicated mask expressions. The following example illustrates the use of the WHERE and ELSEWHERE constructs: REAL, DIMENSION(10) :: A,B WHERE (A<0) WHERE (A< -1.0) B = 1 ELSEWHERE (A < -0.5) B = 3 ENDWHERE ENDWHERE 4.5.12 _O_b_s_o_l_e_s_c_e_n_t _F_e_a_t_u_r_e _D_e_t_e_c_t_i_o_n _f_o_r _F_o_r_t_r_a_n _9_5 Silicon Graphics supports the following FORTRAN 77/Fortran 90 features, even though they have been deleted from the Fortran 95 standard. An - 13 - ANSI message is issued when these features are used. +o Using REAL and DOUBLE PRECISION DO variables +o Branching to an END IF statement from outside its IF block +o Using PAUSE statements +o Using ASSIGN, assigned GOTO, and assigned FORMAT statements +o Using the H edit descriptor Silicon Graphics supports certain other Fortran features, even though the standard has declared them obsolescent. (Obsolescent features are Fortran 90 features that were redundant and for which better methods are available in Fortran 95.) A comment message is issued when these features are used. The following list provides the obsolescent feature with the corresponding preferred feature in parentheses: +o Arithmetic IF (Use the IF statement or the IF construct). +o Shared DO termination and termination on a statement other than an END DO or CONTINUE statement (Use an END DO or CONTINUE statement for each DO statement.) +o Alternate return (Use a return code with a CASE construct upon return). +o Computed GOTO statement (Use the CASE construct). +o Statement functions (Use internal procedures). +o DATA statements among executable statements (Place DATA statements before all executable statements). +o Assumed length character functions (Some uses can be replaced with an automatic character length function, where the length of the function result is declared in a - 14 - specification expression. Other uses can be replaced by the use of a subroutine whose arguments correspond to the function result and the function arguments). +o Fixed source form (Use free source form). +o CHARACTER*char-length form of character declaration (Use CHARACTER*(char-length) or one of the other forms listed in the _F_o_r_t_r_a_n _L_a_n_g_u_a_g_e _R_e_f_e_r_e_n_c_e _M_a_n_u_a_l, Volume 1). 4.5.13 _P_o_i_n_t_e_e_s Pointees can now be of derived type. 4.5.14 _R_u_n_-_T_i_m_e__L_i_n_k_e_r The following options have been added to the _RLD_ARGS environment variable: -f Specifies no re-resolution of symbols that are closed by the dlclose command. This option significantly improves the startup and run time of some applications. This is the default. -s Restores the older rld behavior (some applications will start and run significantly slower with -s set). -idv By default, delay-loaded dynamic shared objects (DSOs) now have their versions checked. This option restores the old behavior of not checking versions. It should not be necessary to set the _RLD_ARGS environment variable. It can be used as a workaround if an application fails. 4.5.15 _S_u_p_e_r_c_o_m_p_u_t_i_n_g__A_P_I__S_u_p_p_o_r_t The MIPSpro 7.3 release supports the Supercomputing Application Programming Interface (API), a set of language features and library functions that are implemented across the - 15 - Silicon Graphics and Cray(TM) product line to meet the application portability needs of high- performance, technical computing customers. For more information, see the online Supercomputing API document at the following URL: http:/www.sgi.com/software/scapi.html