From patchwork Thu Nov 8 18:13:48 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: patch to fix constant math - second small patch Date: Thu, 08 Nov 2012 08:13:48 -0000 From: Kenneth Zadeck X-Patchwork-Id: 197863 Message-Id: <509BF65C.8050905@naturalbridge.com> To: Richard Guenther Cc: Mike Stump , gcc-patches , rdsandiford@googlemail.com I have added the proper doc. OK to commit? Kenny On 10/08/2012 05:06 AM, Richard Guenther wrote: > On Sat, Oct 6, 2012 at 12:48 AM, Kenneth Zadeck > wrote: >> This patch adds machinery to genmodes.c so that largest possible sizes of >> various data structures can be determined at gcc build time. These >> functions create 3 symbols that are available in insn-modes.h: >> MAX_BITSIZE_MODE_INT - the bitsize of the largest int. >> MAX_BITSIZE_MODE_PARTIAL_INT - the bitsize of the largest partial int. >> MAX_BITSIZE_MODE_ANY_INT - the largest bitsize of any kind of int. > Ok. Please document these macros in rtl.texi. > > Richard. 2012-11-8 Kenneth Zadeck * genmodes.c (emit_max_int): New function. (emit_insn_modes_h): Added call to emit_max_function. * doc/rtl.texi (MAX_BITSIZE_MODE_INT, MAX_BITSIZE_MODE_PARTIAL_INT, MAX_BITSIZE_MODE_ANY_INT, MAX_BITSIZE_MODE_ANY_MODE): Added doc. diff --git a/gcc/doc/rtl.texi b/gcc/doc/rtl.texi index 07c480d..6842cb8 100644 --- a/gcc/doc/rtl.texi +++ b/gcc/doc/rtl.texi @@ -1458,6 +1458,28 @@ Returns the number of units contained in a mode, i.e., Returns the narrowest mode in mode class @var{c}. @end table +The following 4 variables are defined on every target. They can be +used to allocate buffers that are guaranteed to be large enough to +hold any value that can be represented on the target. + +@table @code +@findex MAX_BITSIZE_MODE_INT +@item MAX_BITSIZE_MODE_INT +The bitsize of the largest integer mode defined on the target. + +@findex MAX_BITSIZE_MODE_PARTIAL_INT +@item MAX_BITSIZE_MODE_PARTIAL_INT +The bitsize of the largest partial integer mode defined on the target. + +@findex MAX_BITSIZE_MODE_ANY_INT +@item MAX_BITSIZE_MODE_ANY_INT +The maximum of MAX_BITSIZE_MODE_INT and MAX_BITSIZE_MODE_PARTIAL_INT. + +@findex MAX_BITSIZE_MODE_ANY_MODE +@item MAX_BITSIZE_MODE_ANY_MODE +The bitsize of the largest mode on the target. +@end table + @findex byte_mode @findex word_mode The global variables @code{byte_mode} and @code{word_mode} contain modes diff --git a/gcc/genmodes.c b/gcc/genmodes.c index d0095c3..3e63cc7 100644 --- a/gcc/genmodes.c +++ b/gcc/genmodes.c @@ -849,6 +849,38 @@ calc_wider_mode (void) #define print_closer() puts ("};") +/* Compute the max bitsize of some of the classes of integers. It may + be that there are needs for the other integer classes, and this + code is easy to extend. */ +static void +emit_max_int (void) +{ + unsigned int max, mmax; + struct mode_data *i; + int j; + + puts (""); + for (max = 1, i = modes[MODE_INT]; i; i = i->next) + if (max < i->bytesize) + max = i->bytesize; + printf ("#define MAX_BITSIZE_MODE_INT %d*BITS_PER_UNIT\n", max); + mmax = max; + for (max = 1, i = modes[MODE_PARTIAL_INT]; i; i = i->next) + if (max < i->bytesize) + max = i->bytesize; + printf ("#define MAX_BITSIZE_MODE_PARTIAL_INT %d*BITS_PER_UNIT\n", max); + if (max > mmax) + mmax = max; + printf ("#define MAX_BITSIZE_MODE_ANY_INT %d*BITS_PER_UNIT\n", mmax); + + mmax = 0; + for (j = 0; j < MAX_MODE_CLASS; j++) + for (i = modes[j]; i; i = i->next) + if (mmax < i->bytesize) + mmax = i->bytesize; + printf ("#define MAX_BITSIZE_MODE_ANY_MODE %d*BITS_PER_UNIT\n", mmax); +} + static void emit_insn_modes_h (void) { @@ -913,6 +945,7 @@ enum machine_mode\n{"); #endif printf ("#define CONST_MODE_IBIT%s\n", adj_ibit ? "" : " const"); printf ("#define CONST_MODE_FBIT%s\n", adj_fbit ? "" : " const"); + emit_max_int (); puts ("\ \n\ #endif /* insn-modes.h */"); diff --git a/gcc/machmode.def b/gcc/machmode.def index 631015f..7186cb4 100644 --- a/gcc/machmode.def +++ b/gcc/machmode.def @@ -180,8 +180,11 @@ RANDOM_MODE (BLK); FRACTIONAL_INT_MODE (BI, 1, 1); /* Basic integer modes. We go up to TI in generic code (128 bits). - The name OI is reserved for a 256-bit type (needed by some back ends). - FIXME TI shouldn't be generically available either. */ + TImode is needed here because the some front ends now genericly + support __int128. If the front ends decide to generically support + larger types, then corresponding modes must be added here. The + name OI is reserved for a 256-bit type (needed by some back ends). + */ INT_MODE (QI, 1); INT_MODE (HI, 2); INT_MODE (SI, 4);