From: Richard Biener Date: Thu, 25 Jun 2015 14:02:35 +0000 (+0000) Subject: fold-const.c (fold_binary_loc): Move simplification of (X <<>> C1) & C2 ... X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1ffbaa3fec7f3dcbc3d1f999e8fa3f0930b3e1ad;p=gcc.git fold-const.c (fold_binary_loc): Move simplification of (X <<>> C1) & C2 ... 2015-06-25 Richard Biener * fold-const.c (fold_binary_loc): Move simplification of (X <<>> C1) & C2 ... * match.pd: ... here. * gcc.dg/tree-ssa/pr52631.c: Disable forwprop. From-SVN: r224943 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a414549449e..604b7635b06 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2015-06-25 Richard Biener + + * fold-const.c (fold_binary_loc): Move simplification of + (X <<>> C1) & C2 ... + * match.pd: ... here. + 2015-06-25 Eric Botcazou * lto-streamer-out.c (DFS::hash_scc): Fix typos & formatting glitches. diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 60aa2104960..6fa784a17cb 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -11516,106 +11516,6 @@ fold_binary_loc (location_t loc, return build_int_cst (type, residue & low); } - /* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1)) - (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1)) - if the new mask might be further optimized. */ - if ((TREE_CODE (arg0) == LSHIFT_EXPR - || TREE_CODE (arg0) == RSHIFT_EXPR) - && TYPE_PRECISION (TREE_TYPE (arg0)) <= HOST_BITS_PER_WIDE_INT - && TREE_CODE (arg1) == INTEGER_CST - && tree_fits_uhwi_p (TREE_OPERAND (arg0, 1)) - && tree_to_uhwi (TREE_OPERAND (arg0, 1)) > 0 - && (tree_to_uhwi (TREE_OPERAND (arg0, 1)) - < TYPE_PRECISION (TREE_TYPE (arg0)))) - { - unsigned int shiftc = tree_to_uhwi (TREE_OPERAND (arg0, 1)); - unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (arg1); - unsigned HOST_WIDE_INT newmask, zerobits = 0; - tree shift_type = TREE_TYPE (arg0); - - if (TREE_CODE (arg0) == LSHIFT_EXPR) - zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1); - else if (TREE_CODE (arg0) == RSHIFT_EXPR - && TYPE_PRECISION (TREE_TYPE (arg0)) - == GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (arg0)))) - { - prec = TYPE_PRECISION (TREE_TYPE (arg0)); - tree arg00 = TREE_OPERAND (arg0, 0); - /* See if more bits can be proven as zero because of - zero extension. */ - if (TREE_CODE (arg00) == NOP_EXPR - && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg00, 0)))) - { - tree inner_type = TREE_TYPE (TREE_OPERAND (arg00, 0)); - if (TYPE_PRECISION (inner_type) - == GET_MODE_PRECISION (TYPE_MODE (inner_type)) - && TYPE_PRECISION (inner_type) < prec) - { - prec = TYPE_PRECISION (inner_type); - /* See if we can shorten the right shift. */ - if (shiftc < prec) - shift_type = inner_type; - /* Otherwise X >> C1 is all zeros, so we'll optimize - it into (X, 0) later on by making sure zerobits - is all ones. */ - } - } - zerobits = ~(unsigned HOST_WIDE_INT) 0; - if (shiftc < prec) - { - zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc; - zerobits <<= prec - shiftc; - } - /* For arithmetic shift if sign bit could be set, zerobits - can contain actually sign bits, so no transformation is - possible, unless MASK masks them all away. In that - case the shift needs to be converted into logical shift. */ - if (!TYPE_UNSIGNED (TREE_TYPE (arg0)) - && prec == TYPE_PRECISION (TREE_TYPE (arg0))) - { - if ((mask & zerobits) == 0) - shift_type = unsigned_type_for (TREE_TYPE (arg0)); - else - zerobits = 0; - } - } - - /* ((X << 16) & 0xff00) is (X, 0). */ - if ((mask & zerobits) == mask) - return omit_one_operand_loc (loc, type, - build_int_cst (type, 0), arg0); - - newmask = mask | zerobits; - if (newmask != mask && (newmask & (newmask + 1)) == 0) - { - /* Only do the transformation if NEWMASK is some integer - mode's mask. */ - for (prec = BITS_PER_UNIT; - prec < HOST_BITS_PER_WIDE_INT; prec <<= 1) - if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1) - break; - if (prec < HOST_BITS_PER_WIDE_INT - || newmask == ~(unsigned HOST_WIDE_INT) 0) - { - tree newmaskt; - - if (shift_type != TREE_TYPE (arg0)) - { - tem = fold_build2_loc (loc, TREE_CODE (arg0), shift_type, - fold_convert_loc (loc, shift_type, - TREE_OPERAND (arg0, 0)), - TREE_OPERAND (arg0, 1)); - tem = fold_convert_loc (loc, type, tem); - } - else - tem = op0; - newmaskt = build_int_cst_type (TREE_TYPE (op1), newmask); - if (!tree_int_cst_equal (newmaskt, arg1)) - return fold_build2_loc (loc, BIT_AND_EXPR, type, tem, newmaskt); - } - } - } - goto associate; case RDIV_EXPR: diff --git a/gcc/match.pd b/gcc/match.pd index 30383c64944..292ce6d75c6 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -738,6 +738,97 @@ along with GCC; see the file COPYING3. If not see && wi::eq_p (wi::lshift (@0, cand), @2)) (cmp @1 { build_int_cst (TREE_TYPE (@1), cand); }))))) +/* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1)) + (X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1)) + if the new mask might be further optimized. */ +(for shift (lshift rshift) + (simplify + (bit_and (convert?@4 (shift@5 (convert1?@3 @0) INTEGER_CST@1)) INTEGER_CST@2) + (if (tree_nop_conversion_p (TREE_TYPE (@4), TREE_TYPE (@5)) + && TYPE_PRECISION (type) <= HOST_BITS_PER_WIDE_INT + && tree_fits_uhwi_p (@1) + && tree_to_uhwi (@1) > 0 + && tree_to_uhwi (@1) < TYPE_PRECISION (type)) + (with + { + unsigned int shiftc = tree_to_uhwi (@1); + unsigned HOST_WIDE_INT mask = TREE_INT_CST_LOW (@2); + unsigned HOST_WIDE_INT newmask, zerobits = 0; + tree shift_type = TREE_TYPE (@3); + unsigned int prec; + + if (shift == LSHIFT_EXPR) + zerobits = ((((unsigned HOST_WIDE_INT) 1) << shiftc) - 1); + else if (shift == RSHIFT_EXPR + && (TYPE_PRECISION (shift_type) + == GET_MODE_PRECISION (TYPE_MODE (shift_type)))) + { + prec = TYPE_PRECISION (TREE_TYPE (@3)); + tree arg00 = @0; + /* See if more bits can be proven as zero because of + zero extension. */ + if (@3 != @0 + && TYPE_UNSIGNED (TREE_TYPE (@0))) + { + tree inner_type = TREE_TYPE (@0); + if ((TYPE_PRECISION (inner_type) + == GET_MODE_PRECISION (TYPE_MODE (inner_type))) + && TYPE_PRECISION (inner_type) < prec) + { + prec = TYPE_PRECISION (inner_type); + /* See if we can shorten the right shift. */ + if (shiftc < prec) + shift_type = inner_type; + /* Otherwise X >> C1 is all zeros, so we'll optimize + it into (X, 0) later on by making sure zerobits + is all ones. */ + } + } + zerobits = ~(unsigned HOST_WIDE_INT) 0; + if (shiftc < prec) + { + zerobits >>= HOST_BITS_PER_WIDE_INT - shiftc; + zerobits <<= prec - shiftc; + } + /* For arithmetic shift if sign bit could be set, zerobits + can contain actually sign bits, so no transformation is + possible, unless MASK masks them all away. In that + case the shift needs to be converted into logical shift. */ + if (!TYPE_UNSIGNED (TREE_TYPE (@3)) + && prec == TYPE_PRECISION (TREE_TYPE (@3))) + { + if ((mask & zerobits) == 0) + shift_type = unsigned_type_for (TREE_TYPE (@3)); + else + zerobits = 0; + } + } + } + /* ((X << 16) & 0xff00) is (X, 0). */ + (if ((mask & zerobits) == mask) + { build_int_cst (type, 0); }) + (with { newmask = mask | zerobits; } + (if (newmask != mask && (newmask & (newmask + 1)) == 0) + (with + { + /* Only do the transformation if NEWMASK is some integer + mode's mask. */ + for (prec = BITS_PER_UNIT; + prec < HOST_BITS_PER_WIDE_INT; prec <<= 1) + if (newmask == (((unsigned HOST_WIDE_INT) 1) << prec) - 1) + break; + } + (if (prec < HOST_BITS_PER_WIDE_INT + || newmask == ~(unsigned HOST_WIDE_INT) 0) + (with + { tree newmaskt = build_int_cst_type (TREE_TYPE (@2), newmask); } + (if (!tree_int_cst_equal (newmaskt, @2)) + (if (shift_type != TREE_TYPE (@3) + && single_use (@4) && single_use (@5)) + (bit_and (convert (shift:shift_type (convert @3) @1)) { newmaskt; })) + (if (shift_type == TREE_TYPE (@3)) + (bit_and @4 { newmaskt; })))))))))))) + /* Simplifications of conversions. */ /* Basic strip-useless-type-conversions / strip_nops. */ diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 2f3986877d2..b6486ac18e4 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2015-06-25 Richard Biener + + * gcc.dg/tree-ssa/pr52631.c: Disable forwprop. + 2015-06-25 Richard Sandiford * gcc.target/aarch64/vect-add-sub-cond.c: New test. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr52631.c b/gcc/testsuite/gcc.dg/tree-ssa/pr52631.c index 59523ae0ddf..c18a5d570b4 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/pr52631.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr52631.c @@ -1,5 +1,5 @@ /* { dg-do compile } */ -/* { dg-options "-O2 -fdump-tree-fre1-details" } */ +/* { dg-options "-O2 -fno-tree-forwprop -fdump-tree-fre1-details" } */ unsigned f(unsigned a) {