Copyright 2003, 2004, 2005 PathScale, Inc. All Rights Reserved. PathScale EKOPath(TM) Compiler Suite (Fortran, C and C++ compilers) flag descriptions, for SPEC CPU2000 submissions. Portability Flags: -DSPEC_CPU2000_LP64 Compile using LP64 programming model. -DLINUX_i386 Linux Intel system, use "long long" as 64bit variable. -DHAS_ERRLIST Prog env provides specification for "sys_errlist[]". -DFMAX_IS_DOUBLE Specifies whether FMAX is double or float. -DNDEBUG Defining this disables any assert macros used for debugging. -DSPEC_CPU2000_NEED_BOOL Use SPEC provided definition of the boolean type. -DSPEC_CPU2000_LINUX_I386 Compile for an I386 system running Linux. -DPSEC_CPU2000_GLIBC22 Compatibility with 2.2 & later versions of glibc -DSYS_IS_USG Specifies that the operating system is USG compliant. -DSYS_HAS_TIME_PROTO Do not explicitly declare time(). -DSYS_HAS_SIGNAL_PROTO Do not explicitly #include -DSYS_HAS_IOCTL_PROTO Do not explicitly declare ioctl(). -DSYS_HAS_ANSI System is ANSI compliant. -DSYS_HAS_CALLOC_PROTO Do not explicitly declare calloc(). -fixedform tells f90 compiler to use fixed format (F77 72 column format), instead of F90 free format. -DHAVE_SIGNED_CHAR System supports a "signed char" type. -DWANT_STDC_PROTO Use function prototypes as in standard C. Optimization Flags: Some suboptions either enable or disable the feature. To enable a feature, either specify only the suboption name or specify =1, =ON, or =TRUE. Disabling a feature, is accomplished by adding =0, =OFF, or =FALSE. These values are insensitive to case: 'on' & 'ON' mean the same thing. Below, ON & OFF indicate the enabling or disabling of a feature. -CG[:...] Code Generation option group: control the optimizations and transformations of the instruction-level code generator. -CG:cflow=(ON|OFF) A value of OFF disables control flow optimization in the code generation. Default is ON. -CG:gcm=(ON|OFF) Specifying OFF disables the instruction-level global code motion optimization phase. The default is ON. -CG:load_exe=n Specifies the threshold for subsuming a memory load operation into the operand of an arithmetic instruction. The value of 0 turns off this subsumption optimization. The default is 1, when this subsumption is performed only when the result of the load has only one use. This subsumption is not performed if the number of times the result of the load is used exceeds the value n, a non-negative integer. -CG:local_fwd_sched=(ON|OFF) Changes the instruction scheduling algorithm to work forward instead of backward for the instructions in each basic block. The default is OFF. -CG:p2align=(ON|OFF) Align loop heads to 64-byte boundaries. The default is OFF. -CG:p2align_freq=n Aligns branch targets based on execution frequency. This option is meaningful only under feedback-directed compilation. The default value n=0 turns off the alignment optimization. Any other value specifies the frequency threshold at or above which this alignment will be performed by the compiler. -CG:prefetch=(ON|OFF) Turning this OFF suppresses any generation of prefetch instructions in the code generator. This has the same effect as -LNO:prefetch=0. The default is ON which implies using default prefetch algorithms. -CG:prefetchnta=(ON|OFF) Prefetch when data is non-temporal at all levels of the cache hierarchy. This is for data streaming situations in which the data will not need to be re-used soon. The default is OFF. -CG:prefetchnta=(ON|OFF) Prefetch when data is non-temporal at all levels of the cache hierarchy. This is for data streaming situations in which the data will not need to be re-used soon. The default is OFF. -fb_create Used to specify that an instrumented executable program is to be generated. Such an executable is suitable for producing feedback data files with the specified prefix for use in feedback-directed compilation (FDO). The commonly used prefix is "fbdata". This is OFF by default. -fb_opt Used to specify feedback-directed compilation (FDO) by extracting feedback data from files with the specified prefix, which were previously generated using -fb_create. The commonly used prefix is "fbdata". This optimization is off by default. -fb_phase=(0,1,2,3,4) Used to specify the compilation phase at which instrumentation for the collection of profile data is performed, so is useful only when used with -fb_create. The values must be in the range 0 to 4. The default value is 0, and specifies the earliest phase for instrumentation, which is after the front-end processing. -fno-exceptions Tells the compiler that the program does not use exception handling, so it can perform more aggressive optimization in the code. The generation of exception handling constructs is also suppressed. Under this flag, code that uses exception handling cannot be guaranteed to work correctly. Note that the absence of exception handling construct does not mean that the function can be compiled with this flag. For exception handling to work preperly, the scopes crossed between throwing and catching an exception must all have been compiled with exceptions on. -fno-math-errno Do not set ERRNO after calling math functions that are executed with a single instruction, e.g., sqrt. A program that relies on IEEE exceptions for math error handling may want to use this flag for speed while maintaining IEEE arithmetic compatibility. This is implied by -Ofast. The default is -fmath-errno. -GRA:home=(ON|OFF) Turns on or off the rematerialization optimization for non-local user variables in the Global Register Allocator. The default value is ON. -INLINE:aggressive=(ON|OFF) Tells the compiler to be more aggressive about inlining. The default is -INLINE:aggressive=OFF. -IPA[:...] IPA option group: control the inter-procedural analyses and transformations performed. Note that giving just the group name without any options, i.e., -IPA, will invoke the interprocedural analyzer. -IPA is off by default unless -Ofast is specified. -ipa Same as -IPA alone. -IPA:callee_limit=(n) Functions whose size exceeds this limit will never be automatically inlined by the compiler. The default is n=2000. -IPA:ctype=(ON|OFF) Turns on optimizations that speed up interfaces to the constructs defined in ctype.h by assuming that the program will not be run in a multi-threaded environment. The default is OFF. -IPA:field_reorder=(ON|OFF) Enables the re-ordering of fields in large structs based on their reference patterns in feedback compilation to minimize data cache misses. The default is OFF. -IPA:linear=(ON|OFF) Controls conversion of a multi-dimensional array to a single dimensional (linear) array that covers the same block of memory. When inlining Fortran subroutines, IPA tries to map formal array parameters to the shape of the actual parameter. In the case that it cannot map the parameter, it linearizes the array reference. By default, IPA will not inline such callsites because they may cause performance problems. The default is OFF. -IPA:min_hotness=(n) When feedback information is available, a call site to a procedure must be invoked with a frequency that exceeds the threshold specified by n before the procedure will be inlined at that call site. The default is n=10. -IPA:plimit=(n) Inline calls to a procedure until the procedure has grown to size of n. The default is 2500. -IPA:pu_reorder=(0|1|2) Controls the phase that optimizes the layout of the program units (functions) in the program. 0 = Disables procedure reordering (default) 1 = Reorder based on the frequency in which different procedures are invoked. 2 = Reorder based on caller-callee relationship. -IPA:small_pu=(n) A procedure with size smaller than n is not subjected to the plimit restriction.The default is n=30 -IPA:space=(n) Inline until a program expansion of n% is reached. This defaults to 100. -IPA:use_intrinsic[=(ON|OFF)] Enable/disable loading the intrinsic version of standard library functions. The default is OFF. -L/opt/acml2.5.1/pathscale64/lib -lacml The flags above are needed to use the PathScale compiler to link with the ACML (AMD Core Math Library) 2.5.1 library. The PathScale-compiled, 64-bit version of ACML that gets installed at /opt/acml2.0/gnu64 by default. ACML is available as a free download from http://www.developwithamd.com/acml. -LANG:short_circuit_conditionals=(ON|OFF) Handles .AND. and .OR. via short-circuiting, in which the second operand is not evaluated if unnecessary, even if it contains side effects. Applies only to Fortran. Default is ON. -LNO: option group specifies options and transformations performed on loop nests. The -LNO: option group is enabled only if the -O3 option is also specified on the compiler command line. -LNO:blocking[=(ON|OFF)] Enable/disable the cache blocking transformation. The default is on at -O3 or higher. -LNO:fission=(0|1|2) This option controls loop fission. The options can be one of the following: 0 = Disables loop fission (default) 1 = Performs normal fission as necessary 2 = Specifies that fission be tried before fusion If -LNO:fission=1:fusion=1 or -LNO:fission=2:fusion=2 are spec- ified, then fusion is performed. -LNO:full_unroll,fu=N Fully unroll innermost loops with trip_count <= N inside LNO. N can be any integer between 0 and 100. The default value for N is 5. Setting this flag to 0 disables full unrolling of small trip count loops inside LNO. -LNO:full_unroll_size=N Fully unroll innermost loops with unrolled loop size <= N inside LNO. N can be any integer between 0 and 10000. The conditions implied by the full_unroll option must also be satisfied for the loop to be fully unrolled. The default value for N is 1600. -LNO:full_unroll_outer=(ON|OFF) Control the full unrolling of loops with known trip count that do not contain a loop and are not contained in a loop. The conditions implied by both the full_unroll and the full_unroll_size options must be satisfied for the loop to be fully unrolled. The default is OFF. -LNO:fusion=n Perform loop fusion, n: 0 - off, 1 - conservative, 2 - aggressive. The default is 1. -LNO:interchange[=(ON|OFF)] Specifying OFF disables the loop interchange transformation in the loop nest optimizer. Default is ON. -LNO:opt=n This option controls the LNO optimization level. n can be one of the following: 0 = Disables nearly all loop nest optimizations 1 = Performs full loop nest transformations (default) -LNO:ou_prod_max=n Indicates that the product of unrolling of the various outer loops in a given loop nest is not to exceed n, where n is a positive integer. The default is 16. -LNO:outer_unroll_max,ou_max=(n) Outer_unroll_max indicates that the compiler may unroll outer loops in a loop nest by as many as n per loop, but no more. The default is 4. -LNO:prefetch[=(0|1|2|3)] Specify level of prefetching. 0 = Prefetch disabled. 1 = Prefetch is done only for arrays that are always referenced in each iteration of a loop, the default. 2 = Prefetch is done without the above restrictions. 3 = Most aggressive. -LNO:prefetch_ahead=n Prefetch n cache line(s) ahead. The default is 2. -LNO:sclrze=(ON|OFF) Turns on/off the optimization that replaces an array by a scalar variable. The default is ON. -m32 Generates code according to the 32-bit ABI, also known as x86 or IA32. -m3dnow Enable use of 3DNow instructions. The default is OFF. -msse2 Enable SSE2 extension. This is the default under -m64 or -OPT:Ofast. Under -m32, the default is -mno-sse2. -O or -O2 Turn on extensive optimization. The optimizations at this level are generally conservative, in the sense that they (1) are virtually always beneficial, (2) provide improvements commensurate to the compile time spent to achieve them, and (3) avoid changes which affect such things as floating point accuracy. -O3 Turn on aggressive optimization. The optimizations at this level are distinguished from -O2 by their aggressiveness, generally seeking highest-quality generated code even if it requires extensive compile time. They may include optimizations which are generally beneficial but occasionally hurt performance. This includes but is not limited to turning on the Loop Nest Optimizer, -LNO:opt=1, and setting -OPT:ro=1:IEEE_arith=2:Olimit=9000. -Ofast Equivalent to "-O3 -ipa -OPT:Ofast -fno-math-errno." -OPT:Ofast is described below. -OPT:alias= Specifies the pointer aliasing model to be used. By specifiying one or more of the following for , the compiler is able to make assumptions throughout the compilation: typed Assume that the code adheres to the ANSI/ISO C standard which states that two pointers of different types cannot point to the same location in memory. This is on by default when -Ofast is specified. restrict Specifies that distinct pointers are assumed to point to distinct, non-overlapping objects. This is off by default. disjoint Specifies that any two pointer expressions are assumed to point to distinct, non-overlapping objects. This is off by default. -OPT:div_split=(ON|OFF) Enable/disable changing x/y into x*(recip(y)). This is OFF by default but is enabled by -OPT:Ofast or -OPT:IEEE_arithmetic=3. -OPT:fast_complex=(ON|OFF) Setting fast_complex=ON enables fast calculations for values declared to be of type complex. When this is set to ON, complex absolute value (norm) and complex division use fast algorithms that are more likely to overflow or underflow than the standard algorithms. OFF is the default. fast_complex=ON is enabled if -OPT:roundoff=3 is in effect. -OPT:goto=(OFF|ON) Disable/enable the conversion of GOTOs into higher level structures like FOR loops. The default is ON for -O2 or higher. -OPT:IEEE_arithmetic,IEEE_arith=(n) specify level of conformance to IEEE 754 floating pointing roundoff/overflow behavior. n can be one of the following: 1 Adheres to IEEE accuracy. This is the default when optimization levels -O0, -O1 and -O2 are in effect. 2. May produce inexact result not conforming to IEEE 754. This is the default when -O3 is in effect. 3. All mathematically valid transformations are allowed. -OPT:IEEE_NaN_Inf=(ON|OFF) OFF specifies non-IEEE-754 results in operations that might have IEEE 754 NaN or infinity operands; this enables many optimizations which would be invalid for NaN or infinity operands. The default is ON. -OPT:transform_to_memlib=(ON|OFF) When ON, this option enables transformation of loop constructs to calls to memcpy or memset. Default is ON when target processor is EM64T, OFF otherwise. -OPT:Ofast Use optimizations selected to maximize performance. Although the optimizations are generally safe, they may affect floating point accuracy due to rearrangement of computations. This effectively turns on the following optimizations: -OPT:ro=2:Olimit=0:div_split=ON:alias=typed -TARG:msse2=on -OPT:Olimit=(n) Disable optimization when size of program unit is > n. When n is 0, program unit size is ignored and optimization process will not be disabled due to compile time limit. The default is 0 when -Ofast is specified, otherwise the default is 6000 under -O2 and 9000 under -O3. -OPT:roundoff,ro=(n) Specifies the level of acceptable departure from source language floating-point, round-off, and overflow semantics. n can be one of the following: 0 Inhibits optimizations that might affect the floating-point behavior. This is the default when optimization levels -O0, -O1, and -O2 are in effect. 1 Allows simple transformations that might cause limited round-off or overflow differences. Compounding such transformations could have more extensive effects. This is the default level when -O3 is in effect. 2 Allows more extensive transformations, such as the reordering of reduction loops. This is the default level when -Ofast is specified. 3 Enables any mathematically valid transformation. -OPT:treeheight=(ON|OFF) The value ON turns on re-association in expressions to reduce the expressions' tree height. The default value is OFF. -OPT:unroll_analysis=(ON|OFF) The default value of ON lets the compiler analyze the content of the loop to determine the best unrolling parameters, instead of strictly adhering to the -OPT:unroll_times_max and -OPT:unroll_size parameters. -OPT:unroll_times_max,unroll_times=(n) Unroll inner loops by a maximum of n. The default is 4. -OPT:unroll_size=(n) Sets the ceiling of maximum number of instructions for an unrolled inner loop. If n = 0, the ceiling is disregarded. -static Suppresses dynamic linking at run-time for shared libraries; uses static linking instead. -TARG:msse2[=(ON|OFF)] ON enables the use of scalar floating point instructions present in the SSE instruction set. The default is ON for the 64-bit ABI, and OFF for the 32-bit ABI. -TENV:X=(0|1|2|3|4) Specify the level of enabled exceptions that will be assumed for purposes of performing speculative code motion (default is 1 at all optimization levels). In general, an instruction will not be speculated (i.e. moved above a branch by the optimizer) unless any exceptions it might cause are disabled by this option. At level 0, no speculative code motion may be performed. At level 1, safe speculative code motion may be performed, with IEEE-754 underflow and inexact exceptions disabled. At level 2, all IEEE-754 exceptions are disabled except divide by zero. At level 3, all IEEE-754 exceptions are disabled including divide by zero. At level 4, memory exceptions may be disabled or ignored. -TENV:frame_pointer=(ON|OFF) Default is ON for C++ and OFF otherwise. Local variables in the function stack frame are addressed via the frame pointer register. Ordinarily, the compiler will replace this use of frame pointer by addressing local variables via the stack pointer when it determines that the stack pointer is fixed throughout the function invocation. This frees up the frame pointer for other purposes. Turning this flag on forces the compiler to use the frame pointer to address local variables. This flag defaults to on for C++ because the exception handling mechanism relies on the frame pointer register being used to address local variables. This flag can be turned off for C++ for programs that do not throw exceptions. -Wl,-x Passes the -x option to the linker. With this flag set, the linker will not preserve local (non-global) symbols in the output symbol table. The linker enters external and static symbols only. This option conserves space in the output file. This is OFF by default. -WOPT:aggstr=(ON|OFF) ON instructs the scalar optimizer to perform aggressive strength reduction, in which all induction expressions within a loop are replaced by temporaries that are incremented together with the loop variable. When OFF, strength reduction is only performed for non-trivial induction expressions. Turning this off sometimes can improve performance when registers are scarce. -WOPT:if_conv=(ON|OFF) Enables the translation of simple IF statements to condi- tional move instructions in the target CPU. Default is ON. -WOPT:mem_opnds=(ON|OFF) ON makes the scalar optimizer preserve any memory operands of arithmetic operations so as to promote subsumption of memory loads into the operands of arithmetic operations. The default is OFF. -WOPT:retype_expr=(ON|OFF) ON enables the optimization in the compiler that converts 64-bit address computation to use 32-bit arithmetic as much as possible. The default is OFF. -WOPT:val=(0|1|2) Controls the number of times the value-numbering optimization is performed in the global optimizer, with the default being 1. This optimization tries to recognize expressions that will compute identical run-time values and changes the program to avoid re-computing them. ---------------------------------------------------------------------------- Other Notes ---------------------------------------------------------------------------- /usr/bin/taskset [options] [mask] [pid | command [arg] ... ] taskset is used to set or retreive the CPU affinity of a running process given its PID or to launch a new COMMAND with a given CPU affinity. The CPU affinity is represented as a bitmask, with the lowest order bit corresponding to the first logical CPU and highest order bit corresponding to the last logical CPU. When the taskset returns, it is gauranteed that the given program has been scheduled to a legal CPU. The default behaviour of taskset is to run a new command with a given affinity mask: taskset [mask] [command] [arguments] The taskset command is used in the following form in the config file: submit= MYMASK=`printf '0x%x' \$((1<<\$SPECUSERNUM))`; /usr/bin/taskset \$MYMASK $command $MYMASK is the bitmask (in hexadecimal) corresponding to a specific SPECUSERNUM. For example, $MYMASK value for the first copy of a rate run will be 0x00000001, for the second copy of the rate will be 0x00000002 etc. Thus, the first copy of the rate run will have a CPU affinity of CPU0, the second copy will have the affinity CPU1 etc.