From 0ede6b5ad77c4791a513ab312b9e278dafc2bff9 Mon Sep 17 00:00:00 2001 From: Roger Sayle <roger@nextmovesoftware.com> Date: Wed, 31 May 2023 23:40:11 +0100 Subject: [PATCH] Refactor wi::bswap as a function (instead of a method). This patch implements Richard Sandiford's suggestion from https://gcc.gnu.org/pipermail/gcc-patches/2023-May/618215.html that wi::bswap (and a new wi::bitreverse) should be functions, and ideally only accessors are member functions. This patch implements the first step, moving/refactoring wi::bswap. 2023-05-31 Roger Sayle <roger@nextmovesoftware.com> Richard Sandiford <richard.sandiford@arm.com> gcc/ChangeLog * fold-const-call.cc (fold_const_call_ss) <CFN_BUILT_IN_BSWAP*>: Update call to wi::bswap. * simplify-rtx.cc (simplify_const_unary_operation) <case BSWAP>: Update call to wi::bswap. * tree-ssa-ccp.cc (evaluate_stmt) <case BUILT_IN_BSWAP*>: Update calls to wi::bswap. * wide-int.cc (wide_int_storage::bswap): Remove/rename to... (wi::bswap_large): New function, with revised API. * wide-int.h (wi::bswap): New (template) function prototype. (wide_int_storage::bswap): Remove method. (sext_large, zext_large): Consistent indentation/line wrapping. (bswap_large): Prototype helper function containing implementation. (wi::bswap): New template wrapper around bswap_large. --- gcc/fold-const-call.cc | 3 ++- gcc/simplify-rtx.cc | 2 +- gcc/tree-ssa-ccp.cc | 9 +++++---- gcc/wide-int.cc | 18 +++++++----------- gcc/wide-int.h | 28 +++++++++++++++++++++------- 5 files changed, 36 insertions(+), 24 deletions(-) diff --git a/gcc/fold-const-call.cc b/gcc/fold-const-call.cc index 340cb667f6a9..663eae2fa7f7 100644 --- a/gcc/fold-const-call.cc +++ b/gcc/fold-const-call.cc @@ -1060,7 +1060,8 @@ fold_const_call_ss (wide_int *result, combined_fn fn, const wide_int_ref &arg, case CFN_BUILT_IN_BSWAP32: case CFN_BUILT_IN_BSWAP64: case CFN_BUILT_IN_BSWAP128: - *result = wide_int::from (arg, precision, TYPE_SIGN (arg_type)).bswap (); + *result = wi::bswap (wide_int::from (arg, precision, + TYPE_SIGN (arg_type))); return true; default: diff --git a/gcc/simplify-rtx.cc b/gcc/simplify-rtx.cc index 8b48bd3553e8..4e20a3419771 100644 --- a/gcc/simplify-rtx.cc +++ b/gcc/simplify-rtx.cc @@ -2111,7 +2111,7 @@ simplify_const_unary_operation (enum rtx_code code, machine_mode mode, break; case BSWAP: - result = wide_int (op0).bswap (); + result = wi::bswap (op0); break; case TRUNCATE: diff --git a/gcc/tree-ssa-ccp.cc b/gcc/tree-ssa-ccp.cc index 6fb371c26297..26d5e445abd5 100644 --- a/gcc/tree-ssa-ccp.cc +++ b/gcc/tree-ssa-ccp.cc @@ -2401,11 +2401,12 @@ evaluate_stmt (gimple *stmt) wide_int wval = wi::to_wide (val.value); val.value = wide_int_to_tree (type, - wide_int::from (wval, prec, - UNSIGNED).bswap ()); + wi::bswap (wide_int::from (wval, prec, + UNSIGNED))); val.mask - = widest_int::from (wide_int::from (val.mask, prec, - UNSIGNED).bswap (), + = widest_int::from (wi::bswap (wide_int::from (val.mask, + prec, + UNSIGNED)), UNSIGNED); if (wi::sext (val.mask, prec) != -1) break; diff --git a/gcc/wide-int.cc b/gcc/wide-int.cc index c0987aa4d63a..1e4c0460b743 100644 --- a/gcc/wide-int.cc +++ b/gcc/wide-int.cc @@ -731,16 +731,13 @@ wi::set_bit_large (HOST_WIDE_INT *val, const HOST_WIDE_INT *xval, } } -/* bswap THIS. */ -wide_int -wide_int_storage::bswap () const +/* Byte swap the integer represented by XVAL and LEN into VAL. Return + the number of blocks in VAL. Both XVAL and VAL have PRECISION bits. */ +unsigned int +wi::bswap_large (HOST_WIDE_INT *val, const HOST_WIDE_INT *xval, + unsigned int len, unsigned int precision) { - wide_int result = wide_int::create (precision); unsigned int i, s; - unsigned int len = BLOCKS_NEEDED (precision); - unsigned int xlen = get_len (); - const HOST_WIDE_INT *xval = get_val (); - HOST_WIDE_INT *val = result.write_val (); /* This is not a well defined operation if the precision is not a multiple of 8. */ @@ -758,7 +755,7 @@ wide_int_storage::bswap () const unsigned int block = s / HOST_BITS_PER_WIDE_INT; unsigned int offset = s & (HOST_BITS_PER_WIDE_INT - 1); - byte = (safe_uhwi (xval, xlen, block) >> offset) & 0xff; + byte = (safe_uhwi (xval, len, block) >> offset) & 0xff; block = d / HOST_BITS_PER_WIDE_INT; offset = d & (HOST_BITS_PER_WIDE_INT - 1); @@ -766,8 +763,7 @@ wide_int_storage::bswap () const val[block] |= byte << offset; } - result.set_len (canonize (val, len, precision)); - return result; + return canonize (val, len, precision); } /* Fill VAL with a mask where the lower WIDTH bits are ones and the bits diff --git a/gcc/wide-int.h b/gcc/wide-int.h index 3d9b87cd91a1..e4723adce2c8 100644 --- a/gcc/wide-int.h +++ b/gcc/wide-int.h @@ -552,6 +552,7 @@ namespace wi UNARY_FUNCTION sext (const T &, unsigned int); UNARY_FUNCTION zext (const T &, unsigned int); UNARY_FUNCTION set_bit (const T &, unsigned int); + UNARY_FUNCTION bswap (const T &); BINARY_FUNCTION min (const T1 &, const T2 &, signop); BINARY_FUNCTION smin (const T1 &, const T2 &); @@ -1086,9 +1087,6 @@ public: static wide_int from_array (const HOST_WIDE_INT *, unsigned int, unsigned int, bool = true); static wide_int create (unsigned int); - - /* FIXME: target-dependent, so should disappear. */ - wide_int bswap () const; }; namespace wi @@ -1743,13 +1741,14 @@ namespace wi int cmpu_large (const HOST_WIDE_INT *, unsigned int, unsigned int, const HOST_WIDE_INT *, unsigned int); unsigned int sext_large (HOST_WIDE_INT *, const HOST_WIDE_INT *, - unsigned int, - unsigned int, unsigned int); + unsigned int, unsigned int, unsigned int); unsigned int zext_large (HOST_WIDE_INT *, const HOST_WIDE_INT *, - unsigned int, - unsigned int, unsigned int); + unsigned int, unsigned int, unsigned int); unsigned int set_bit_large (HOST_WIDE_INT *, const HOST_WIDE_INT *, unsigned int, unsigned int, unsigned int); + unsigned int bswap_large (HOST_WIDE_INT *, const HOST_WIDE_INT *, + unsigned int, unsigned int); + unsigned int lshift_large (HOST_WIDE_INT *, const HOST_WIDE_INT *, unsigned int, unsigned int, unsigned int); unsigned int lrshift_large (HOST_WIDE_INT *, const HOST_WIDE_INT *, @@ -2267,6 +2266,21 @@ wi::set_bit (const T &x, unsigned int bit) return result; } +/* Byte swap the integer X. + ??? This always swaps 8-bit octets, regardless of BITS_PER_UNIT. + This function requires X's precision to be a multiple of 16 bits, + so care needs to be taken for targets where BITS_PER_UNIT != 8. */ +template <typename T> +inline WI_UNARY_RESULT (T) +wi::bswap (const T &x) +{ + WI_UNARY_RESULT_VAR (result, val, T, x); + unsigned int precision = get_precision (result); + WIDE_INT_REF_FOR (T) xi (x, precision); + result.set_len (bswap_large (val, xi.val, xi.len, precision)); + return result; +} + /* Return the mininum of X and Y, treating them both as having signedness SGN. */ template <typename T1, typename T2> -- GitLab