Changes since v4: - Changed the condition register mode to CC; - Fixed some style issues (removed spaces between operands in asm, included spaces after function names in the testcases and before sentences in the manual)
-- >8 -- Add __builtin_ppc_get_timebase and __builtin_ppc_mftb to read the Time Base Register on PowerPC. They are required by applications that measure time at high frequencies with high precision that can't afford a syscall. __builtin_ppc_get_timebase returns the 64 bits of the Time Base Register while __builtin_ppc_mftb generates only 1 instruction and returns the least significant word on 32-bit environments and the whole Time Base value on 64-bit. [gcc] 2012-09-19 Tulio Magno Quites Machado Filho <tul...@linux.vnet.ibm.com> * config/rs6000/rs6000-builtin.def: Add __builtin_ppc_get_timebase and __builtin_ppc_mftb. * config/rs6000/rs6000.c (rs6000_expand_zeroop_builtin): New function to expand an expression that calls a built-in without arguments. (rs6000_expand_builtin): Add __builtin_ppc_get_timebase and __builtin_ppc_mftb. (rs6000_init_builtins): Likewise. * config/rs6000/rs6000.md: Likewise. * doc/extend.texi (PowerPC Built-in Functions): New section. (PowerPC AltiVec/VSX Built-in Functions): Move some built-ins unrelated to Altivec/VSX to the new section. [gcc/testsuite] 2012-09-19 Tulio Magno Quites Machado Filho <tul...@linux.vnet.ibm.com> * gcc.target/powerpc/ppc-get-timebase.c: New file. * gcc.target/powerpc/ppc-mftb.c: New file. --- gcc/config/rs6000/rs6000-builtin.def | 6 ++ gcc/config/rs6000/rs6000.c | 46 ++++++++++++++ gcc/config/rs6000/rs6000.md | 66 ++++++++++++++++++++ gcc/doc/extend.texi | 51 ++++++++++----- .../gcc.target/powerpc/ppc-get-timebase.c | 20 ++++++ gcc/testsuite/gcc.target/powerpc/ppc-mftb.c | 18 +++++ 6 files changed, 189 insertions(+), 18 deletions(-) create mode 100644 gcc/testsuite/gcc.target/powerpc/ppc-get-timebase.c create mode 100644 gcc/testsuite/gcc.target/powerpc/ppc-mftb.c diff --git a/gcc/config/rs6000/rs6000-builtin.def b/gcc/config/rs6000/rs6000-builtin.def index c8f8f86..9fa3a0f 100644 --- a/gcc/config/rs6000/rs6000-builtin.def +++ b/gcc/config/rs6000/rs6000-builtin.def @@ -1429,6 +1429,12 @@ BU_SPECIAL_X (RS6000_BUILTIN_RSQRT, "__builtin_rsqrt", RS6000_BTM_FRSQRTE, BU_SPECIAL_X (RS6000_BUILTIN_RSQRTF, "__builtin_rsqrtf", RS6000_BTM_FRSQRTES, RS6000_BTC_FP) +BU_SPECIAL_X (RS6000_BUILTIN_GET_TB, "__builtin_ppc_get_timebase", + RS6000_BTM_ALWAYS, RS6000_BTC_MISC) + +BU_SPECIAL_X (RS6000_BUILTIN_MFTB, "__builtin_ppc_mftb", + RS6000_BTM_ALWAYS, RS6000_BTC_MISC) + /* Darwin CfString builtin. */ BU_SPECIAL_X (RS6000_BUILTIN_CFSTRING, "__builtin_cfstring", RS6000_BTM_ALWAYS, RS6000_BTC_MISC) diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c index a5a3848..c3bece1 100644 --- a/gcc/config/rs6000/rs6000.c +++ b/gcc/config/rs6000/rs6000.c @@ -9748,6 +9748,30 @@ rs6000_overloaded_builtin_p (enum rs6000_builtins fncode) return (rs6000_builtin_info[(int)fncode].attr & RS6000_BTC_OVERLOADED) != 0; } +/* Expand an expression EXP that calls a builtin without arguments. */ +static rtx +rs6000_expand_zeroop_builtin (enum insn_code icode, rtx target) +{ + rtx pat; + enum machine_mode tmode = insn_data[icode].operand[0].mode; + + if (icode == CODE_FOR_nothing) + /* Builtin not supported on this processor. */ + return 0; + + if (target == 0 + || GET_MODE (target) != tmode + || ! (*insn_data[icode].operand[0].predicate) (target, tmode)) + target = gen_reg_rtx (tmode); + + pat = GEN_FCN (icode) (target); + if (! pat) + return 0; + emit_insn (pat); + + return target; +} + static rtx rs6000_expand_unop_builtin (enum insn_code icode, tree exp, rtx target) @@ -11337,6 +11361,16 @@ rs6000_expand_builtin (tree exp, rtx target, rtx subtarget ATTRIBUTE_UNUSED, ? CODE_FOR_bpermd_di : CODE_FOR_bpermd_si), exp, target); + case RS6000_BUILTIN_GET_TB: + return rs6000_expand_zeroop_builtin (CODE_FOR_rs6000_get_timebase, + target); + + case RS6000_BUILTIN_MFTB: + return rs6000_expand_zeroop_builtin (((TARGET_64BIT) + ? CODE_FOR_rs6000_mftb_di + : CODE_FOR_rs6000_mftb_si), + target); + case ALTIVEC_BUILTIN_MASK_FOR_LOAD: case ALTIVEC_BUILTIN_MASK_FOR_STORE: { @@ -11621,6 +11655,18 @@ rs6000_init_builtins (void) POWER7_BUILTIN_BPERMD, "__builtin_bpermd"); def_builtin ("__builtin_bpermd", ftype, POWER7_BUILTIN_BPERMD); + ftype = build_function_type_list (unsigned_intDI_type_node, + NULL_TREE); + def_builtin ("__builtin_ppc_get_timebase", ftype, RS6000_BUILTIN_GET_TB); + + if (TARGET_64BIT) + ftype = build_function_type_list (unsigned_intDI_type_node, + NULL_TREE); + else + ftype = build_function_type_list (unsigned_intSI_type_node, + NULL_TREE); + def_builtin ("__builtin_ppc_mftb", ftype, RS6000_BUILTIN_MFTB); + #if TARGET_XCOFF /* AIX libm provides clog as __clog. */ if ((tdecl = builtin_decl_explicit (BUILT_IN_CLOG)) != NULL_TREE) diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md index f2bc15f..c499156 100644 --- a/gcc/config/rs6000/rs6000.md +++ b/gcc/config/rs6000/rs6000.md @@ -136,6 +136,7 @@ UNSPECV_PROBE_STACK_RANGE ; probe range of stack addresses UNSPECV_EH_RR ; eh_reg_restore UNSPECV_ISYNC ; isync instruction + UNSPECV_MFTB ; move from time base ]) @@ -14103,6 +14104,71 @@ "" "") +(define_expand "rs6000_get_timebase" + [(use (match_operand:DI 0 "gpc_reg_operand" ""))] + "" +{ + if (TARGET_POWERPC64) + emit_insn (gen_rs6000_mftb_di (operands[0])); + else + emit_insn (gen_rs6000_get_timebase_ppc32 (operands[0])); + DONE; +}) + +(define_insn "rs6000_get_timebase_ppc32" + [(set (match_operand:DI 0 "gpc_reg_operand" "=r") + (unspec_volatile:DI [(const_int 0)] UNSPECV_MFTB)) + (clobber (match_scratch:SI 1 "=r")) + (clobber (match_scratch:CC 2 "=y"))] + "!TARGET_POWERPC64" +{ + if (WORDS_BIG_ENDIAN) + if (TARGET_MFCRF) + { + return "mfspr %0,269\;" + "mfspr %L0,268\;" + "mfspr %1,269\;" + "cmpw %2,%0, %1\;" + "bne- %2,$-16"; + } + else + { + return "mftbu %0\;" + "mftb %L0\;" + "mftbu %1\;" + "cmpw %2,%0,%1\;" + "bne- %2,$-16"; + } + else + if (TARGET_MFCRF) + { + return "mfspr %L0,269\;" + "mfspr %0,268\;" + "mfspr %1,269\;" + "cmpw %2,%L0,%1\;" + "bne- %2,$-16"; + } + else + { + return "mftbu %L0\;" + "mftb %0\;" + "mftbu %1\;" + "cmpw %2,%L0,%1\;" + "bne- %2,$-16"; + } +}) + +(define_insn "rs6000_mftb_<mode>" + [(set (match_operand:P 0 "gpc_reg_operand" "=r") + (unspec_volatile:P [(const_int 0)] UNSPECV_MFTB))] + "" +{ + if (TARGET_MFCRF) + return "mfspr %0,268"; + else + return "mftb %0"; +}) + (include "sync.md") diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi index e850266..5a75d45 100644 --- a/gcc/doc/extend.texi +++ b/gcc/doc/extend.texi @@ -8647,6 +8647,7 @@ instructions, but allow the compiler to schedule those calls. * MIPS Loongson Built-in Functions:: * Other MIPS Built-in Functions:: * picoChip Built-in Functions:: +* PowerPC Built-in Functions:: * PowerPC AltiVec/VSX Built-in Functions:: * RX Built-in Functions:: * SPARC VIS Built-in Functions:: @@ -11596,6 +11597,38 @@ GCC defines the preprocessor macro @code{___GCC_HAVE_BUILTIN_MIPS_CACHE} when this function is available. @end table +@node PowerPC Built-in Functions +@subsection PowerPC Built-in Functions + +These built-in functions are available for the PowerPC family of +processors: +@smallexample +float __builtin_recipdivf (float, float); +float __builtin_rsqrtf (float); +double __builtin_recipdiv (double, double); +double __builtin_rsqrt (double); +long __builtin_bpermd (long, long); +uint64_t __builtin_ppc_get_timebase (); +unsigned long __builtin_ppc_mftb (); +@end smallexample + +The @code{vec_rsqrt}, @code{__builtin_rsqrt}, and +@code{__builtin_rsqrtf} functions generate multiple instructions to +implement the reciprocal sqrt functionality using reciprocal sqrt +estimate instructions. + +The @code{__builtin_recipdiv}, and @code{__builtin_recipdivf} +functions generate multiple instructions to implement division using +the reciprocal estimate instructions. + +The @code{__builtin_ppc_get_timebase} and @code{__builtin_ppc_mftb} +functions generate instructions to read the Time Base Register. The +@code{__builtin_ppc_get_timebase} function may generate multiple +instructions and always returns the 64 bits of the Time Base Register. +The @code{__builtin_ppc_mftb} function always generates one instruction and +returns the Time Base Register value as an unsigned long, throwing away +the most significant word on 32-bit environments. + @node PowerPC AltiVec/VSX Built-in Functions @subsection PowerPC AltiVec Built-in Functions @@ -13653,24 +13686,6 @@ if the VSX instruction set is available. The @samp{vec_vsx_ld} and @samp{vec_vsx_st} builtins will always generate the VSX @samp{LXVD2X}, @samp{LXVW4X}, @samp{STXVD2X}, and @samp{STXVW4X} instructions. -GCC provides a few other builtins on Powerpc to access certain instructions: -@smallexample -float __builtin_recipdivf (float, float); -float __builtin_rsqrtf (float); -double __builtin_recipdiv (double, double); -double __builtin_rsqrt (double); -long __builtin_bpermd (long, long); -@end smallexample - -The @code{vec_rsqrt}, @code{__builtin_rsqrt}, and -@code{__builtin_rsqrtf} functions generate multiple instructions to -implement the reciprocal sqrt functionality using reciprocal sqrt -estimate instructions. - -The @code{__builtin_recipdiv}, and @code{__builtin_recipdivf} -functions generate multiple instructions to implement division using -the reciprocal estimate instructions. - @node RX Built-in Functions @subsection RX Built-in Functions GCC supports some of the RX instructions which cannot be expressed in diff --git a/gcc/testsuite/gcc.target/powerpc/ppc-get-timebase.c b/gcc/testsuite/gcc.target/powerpc/ppc-get-timebase.c new file mode 100644 index 0000000..9de8929 --- /dev/null +++ b/gcc/testsuite/gcc.target/powerpc/ppc-get-timebase.c @@ -0,0 +1,20 @@ +/* { dg-do run { target { powerpc*-*-* } } } */ + +/* Test if __builtin_ppc_get_timebase () is compatible with the current + processor and if it's changing between reads. A read failure might indicate + a Power ISA or binutils change. */ + +#include <inttypes.h> + +int +main (void) +{ + uint64_t t = __builtin_ppc_get_timebase (); + int j; + + for (j = 0; j < 1000000; j++) + if (t != __builtin_ppc_get_timebase ()) + return 0; + + return 1; +} diff --git a/gcc/testsuite/gcc.target/powerpc/ppc-mftb.c b/gcc/testsuite/gcc.target/powerpc/ppc-mftb.c new file mode 100644 index 0000000..f64e45d --- /dev/null +++ b/gcc/testsuite/gcc.target/powerpc/ppc-mftb.c @@ -0,0 +1,18 @@ +/* { dg-do run { target { powerpc*-*-* } } } */ + +/* Test if __builtin_ppc_mftb () is compatible with the current processor and + if it's changing between reads. A read failure might indicate a Power + ISA or binutils change. */ + +int +main (void) +{ + unsigned long t = __builtin_ppc_mftb (); + int j; + + for (j = 0; j < 1000000; j++) + if (t != __builtin_ppc_mftb ()) + return 0; + + return 1; +} -- 1.7.7.6