On Thu, 5 Jul 2018, Jakub Jelinek wrote:
> Hi!
>
> I've encountered this while testing the rotate patterns in discussion
> with Jonathan for the std::__rot{l,r}, in the rotate-9.c test without
> this patch f1 is optimized into a rotate, but f2 is not.
>
> Fixed by moving the optimization from fold-const.c to match.pd (well,
> leaving a helper in fold-const.c to avoid too much duplication).
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
OK.
Thanks,
Richard.
> 2018-07-05 Jakub Jelinek <ja...@redhat.com>
>
> PR tree-optimization/86401
> * fold-const.c (fold_binary_loc) <case BIT_AND_EXPR>: Move the
> ((A & N) + B) & M -> (A + B) & M etc. optimization into ...
> (fold_bit_and_mask): ... here. New helper function for match.pd.
> * fold-const.h (fold_bit_and_mask): Declare.
> * match.pd (((A & N) + B) & M -> (A + B) & M): New optimization.
>
> * gcc.dg/tree-ssa/pr86401-1.c: New test.
> * gcc.dg/tree-ssa/pr86401-2.c: New test.
> * c-c++-common/rotate-9.c: New test.
>
> --- gcc/fold-const.c.jj 2018-06-26 09:05:23.196346433 +0200
> +++ gcc/fold-const.c 2018-07-04 12:47:59.139981801 +0200
> @@ -10236,121 +10236,6 @@ fold_binary_loc (location_t loc, enum tr
> }
> }
>
> - /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
> - ((A & N) + B) & M -> (A + B) & M
> - Similarly if (N & M) == 0,
> - ((A | N) + B) & M -> (A + B) & M
> - and for - instead of + (or unary - instead of +)
> - and/or ^ instead of |.
> - If B is constant and (B & M) == 0, fold into A & M. */
> - if (TREE_CODE (arg1) == INTEGER_CST)
> - {
> - wi::tree_to_wide_ref cst1 = wi::to_wide (arg1);
> - if ((~cst1 != 0) && (cst1 & (cst1 + 1)) == 0
> - && INTEGRAL_TYPE_P (TREE_TYPE (arg0))
> - && (TREE_CODE (arg0) == PLUS_EXPR
> - || TREE_CODE (arg0) == MINUS_EXPR
> - || TREE_CODE (arg0) == NEGATE_EXPR)
> - && (TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0))
> - || TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE))
> - {
> - tree pmop[2];
> - int which = 0;
> - wide_int cst0;
> -
> - /* Now we know that arg0 is (C + D) or (C - D) or
> - -C and arg1 (M) is == (1LL << cst) - 1.
> - Store C into PMOP[0] and D into PMOP[1]. */
> - pmop[0] = TREE_OPERAND (arg0, 0);
> - pmop[1] = NULL;
> - if (TREE_CODE (arg0) != NEGATE_EXPR)
> - {
> - pmop[1] = TREE_OPERAND (arg0, 1);
> - which = 1;
> - }
> -
> - if ((wi::max_value (TREE_TYPE (arg0)) & cst1) != cst1)
> - which = -1;
> -
> - for (; which >= 0; which--)
> - switch (TREE_CODE (pmop[which]))
> - {
> - case BIT_AND_EXPR:
> - case BIT_IOR_EXPR:
> - case BIT_XOR_EXPR:
> - if (TREE_CODE (TREE_OPERAND (pmop[which], 1))
> - != INTEGER_CST)
> - break;
> - cst0 = wi::to_wide (TREE_OPERAND (pmop[which], 1)) & cst1;
> - if (TREE_CODE (pmop[which]) == BIT_AND_EXPR)
> - {
> - if (cst0 != cst1)
> - break;
> - }
> - else if (cst0 != 0)
> - break;
> - /* If C or D is of the form (A & N) where
> - (N & M) == M, or of the form (A | N) or
> - (A ^ N) where (N & M) == 0, replace it with A. */
> - pmop[which] = TREE_OPERAND (pmop[which], 0);
> - break;
> - case INTEGER_CST:
> - /* If C or D is a N where (N & M) == 0, it can be
> - omitted (assumed 0). */
> - if ((TREE_CODE (arg0) == PLUS_EXPR
> - || (TREE_CODE (arg0) == MINUS_EXPR && which == 0))
> - && (cst1 & wi::to_wide (pmop[which])) == 0)
> - pmop[which] = NULL;
> - break;
> - default:
> - break;
> - }
> -
> - /* Only build anything new if we optimized one or both arguments
> - above. */
> - if (pmop[0] != TREE_OPERAND (arg0, 0)
> - || (TREE_CODE (arg0) != NEGATE_EXPR
> - && pmop[1] != TREE_OPERAND (arg0, 1)))
> - {
> - tree utype = TREE_TYPE (arg0);
> - if (! TYPE_OVERFLOW_WRAPS (TREE_TYPE (arg0)))
> - {
> - /* Perform the operations in a type that has defined
> - overflow behavior. */
> - utype = unsigned_type_for (TREE_TYPE (arg0));
> - if (pmop[0] != NULL)
> - pmop[0] = fold_convert_loc (loc, utype, pmop[0]);
> - if (pmop[1] != NULL)
> - pmop[1] = fold_convert_loc (loc, utype, pmop[1]);
> - }
> -
> - if (TREE_CODE (arg0) == NEGATE_EXPR)
> - tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[0]);
> - else if (TREE_CODE (arg0) == PLUS_EXPR)
> - {
> - if (pmop[0] != NULL && pmop[1] != NULL)
> - tem = fold_build2_loc (loc, PLUS_EXPR, utype,
> - pmop[0], pmop[1]);
> - else if (pmop[0] != NULL)
> - tem = pmop[0];
> - else if (pmop[1] != NULL)
> - tem = pmop[1];
> - else
> - return build_int_cst (type, 0);
> - }
> - else if (pmop[0] == NULL)
> - tem = fold_build1_loc (loc, NEGATE_EXPR, utype, pmop[1]);
> - else
> - tem = fold_build2_loc (loc, MINUS_EXPR, utype,
> - pmop[0], pmop[1]);
> - /* TEM is now the new binary +, - or unary - replacement. */
> - tem = fold_build2_loc (loc, BIT_AND_EXPR, utype, tem,
> - fold_convert_loc (loc, utype, arg1));
> - return fold_convert_loc (loc, type, tem);
> - }
> - }
> - }
> -
> /* Simplify ((int)c & 0377) into (int)c, if c is unsigned char. */
> if (TREE_CODE (arg1) == INTEGER_CST && TREE_CODE (arg0) == NOP_EXPR
> && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
> @@ -11264,6 +11149,100 @@ fold_binary_loc (location_t loc, enum tr
> } /* switch (code) */
> }
>
> +/* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
> + ((A & N) + B) & M -> (A + B) & M
> + Similarly if (N & M) == 0,
> + ((A | N) + B) & M -> (A + B) & M
> + and for - instead of + (or unary - instead of +)
> + and/or ^ instead of |.
> + If B is constant and (B & M) == 0, fold into A & M.
> +
> + This function is a helper for match.pd patterns. Return non-NULL
> + type in which the simplified operation should be performed only
> + if any optimization is possible.
> +
> + ARG1 is M above, ARG00 is left operand of +/-, if CODE00 is BIT_*_EXPR,
> + then ARG00{0,1} are operands of that bitop, otherwise CODE00 is
> ERROR_MARK.
> + Similarly for ARG01, CODE01 and ARG01{0,1}, just for the right operand of
> + +/-. */
> +tree
> +fold_bit_and_mask (tree type, tree arg1, enum tree_code code,
> + tree arg00, enum tree_code code00, tree arg000, tree arg001,
> + tree arg01, enum tree_code code01, tree arg010, tree arg011,
> + tree *pmop)
> +{
> + gcc_assert (TREE_CODE (arg1) == INTEGER_CST);
> + gcc_assert (code == PLUS_EXPR || code == MINUS_EXPR || code ==
> NEGATE_EXPR);
> + wi::tree_to_wide_ref cst1 = wi::to_wide (arg1);
> + if (~cst1 == 0
> + || (cst1 & (cst1 + 1)) != 0
> + || !INTEGRAL_TYPE_P (type)
> + || (!TYPE_OVERFLOW_WRAPS (type)
> + && TREE_CODE (type) != INTEGER_TYPE)
> + || (wi::max_value (type) & cst1) != cst1)
> + return NULL_TREE;
> +
> + enum tree_code codes[2] = { code00, code01 };
> + tree arg0xx[4] = { arg000, arg001, arg010, arg011 };
> + int which = 0;
> + wide_int cst0;
> +
> + /* Now we know that arg0 is (C + D) or (C - D) or -C and
> + arg1 (M) is == (1LL << cst) - 1.
> + Store C into PMOP[0] and D into PMOP[1]. */
> + pmop[0] = arg00;
> + pmop[1] = arg01;
> + which = code != NEGATE_EXPR;
> +
> + for (; which >= 0; which--)
> + switch (codes[which])
> + {
> + case BIT_AND_EXPR:
> + case BIT_IOR_EXPR:
> + case BIT_XOR_EXPR:
> + gcc_assert (TREE_CODE (arg0xx[2 * which + 1]) == INTEGER_CST);
> + cst0 = wi::to_wide (arg0xx[2 * which + 1]) & cst1;
> + if (codes[which] == BIT_AND_EXPR)
> + {
> + if (cst0 != cst1)
> + break;
> + }
> + else if (cst0 != 0)
> + break;
> + /* If C or D is of the form (A & N) where
> + (N & M) == M, or of the form (A | N) or
> + (A ^ N) where (N & M) == 0, replace it with A. */
> + pmop[which] = arg0xx[2 * which];
> + break;
> + case ERROR_MARK:
> + if (TREE_CODE (pmop[which]) != INTEGER_CST)
> + break;
> + /* If C or D is a N where (N & M) == 0, it can be
> + omitted (replaced with 0). */
> + if ((code == PLUS_EXPR
> + || (code == MINUS_EXPR && which == 0))
> + && (cst1 & wi::to_wide (pmop[which])) == 0)
> + pmop[which] = build_int_cst (type, 0);
> + /* Similarly, with C - N where (-N & M) == 0. */
> + if (code == MINUS_EXPR
> + && which == 1
> + && (cst1 & -wi::to_wide (pmop[which])) == 0)
> + pmop[which] = build_int_cst (type, 0);
> + break;
> + default:
> + gcc_unreachable ();
> + }
> +
> + /* Only build anything new if we optimized one or both arguments above. */
> + if (pmop[0] == arg00 && pmop[1] == arg01)
> + return NULL_TREE;
> +
> + if (TYPE_OVERFLOW_WRAPS (type))
> + return type;
> + else
> + return unsigned_type_for (type);
> +}
> +
> /* Used by contains_label_[p1]. */
>
> struct contains_label_data
> --- gcc/fold-const.h.jj 2018-05-25 14:34:36.871377394 +0200
> +++ gcc/fold-const.h 2018-07-04 12:34:18.072910936 +0200
> @@ -96,6 +96,9 @@ extern tree omit_two_operands_loc (locat
> extern tree invert_truthvalue_loc (location_t, tree);
> extern tree fold_unary_to_constant (enum tree_code, tree, tree);
> extern tree fold_binary_to_constant (enum tree_code, tree, tree, tree);
> +extern tree fold_bit_and_mask (tree, tree, enum tree_code,
> + tree, enum tree_code, tree, tree,
> + tree, enum tree_code, tree, tree, tree *);
> extern tree fold_read_from_constant_string (tree);
> extern tree int_const_binop (enum tree_code, const_tree, const_tree);
> #define build_fold_addr_expr(T)\
> --- gcc/match.pd.jj 2018-06-20 08:15:34.196862169 +0200
> +++ gcc/match.pd 2018-07-04 13:21:07.897317459 +0200
> @@ -779,6 +779,60 @@ (define_operator_list COND_BINARY
> (bit_xor @0 @1)))
> #endif
>
> +/* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
> + ((A & N) + B) & M -> (A + B) & M
> + Similarly if (N & M) == 0,
> + ((A | N) + B) & M -> (A + B) & M
> + and for - instead of + (or unary - instead of +)
> + and/or ^ instead of |.
> + If B is constant and (B & M) == 0, fold into A & M. */
> +(for op (plus minus)
> + (for bitop (bit_and bit_ior bit_xor)
> + (simplify
> + (bit_and (op:s (bitop:s@0 @3 INTEGER_CST@4) @1) INTEGER_CST@2)
> + (with
> + { tree pmop[2];
> + tree utype = fold_bit_and_mask (TREE_TYPE (@0), @2, op, @0, bitop,
> + @3, @4, @1, ERROR_MARK, NULL_TREE,
> + NULL_TREE, pmop); }
> + (if (utype)
> + (convert (bit_and (op (convert:utype { pmop[0]; })
> + (convert:utype { pmop[1]; }))
> + (convert:utype @2))))))
> + (simplify
> + (bit_and (op:s @0 (bitop:s@1 @3 INTEGER_CST@4)) INTEGER_CST@2)
> + (with
> + { tree pmop[2];
> + tree utype = fold_bit_and_mask (TREE_TYPE (@0), @2, op, @0,
> ERROR_MARK,
> + NULL_TREE, NULL_TREE, @1, bitop, @3,
> + @4, pmop); }
> + (if (utype)
> + (convert (bit_and (op (convert:utype { pmop[0]; })
> + (convert:utype { pmop[1]; }))
> + (convert:utype @2)))))))
> + (simplify
> + (bit_and (op:s @0 @1) INTEGER_CST@2)
> + (with
> + { tree pmop[2];
> + tree utype = fold_bit_and_mask (TREE_TYPE (@0), @2, op, @0, ERROR_MARK,
> + NULL_TREE, NULL_TREE, @1, ERROR_MARK,
> + NULL_TREE, NULL_TREE, pmop); }
> + (if (utype)
> + (convert (bit_and (op (convert:utype { pmop[0]; })
> + (convert:utype { pmop[1]; }))
> + (convert:utype @2)))))))
> +(for bitop (bit_and bit_ior bit_xor)
> + (simplify
> + (bit_and (negate:s (bitop:s@0 @2 INTEGER_CST@3)) INTEGER_CST@1)
> + (with
> + { tree pmop[2];
> + tree utype = fold_bit_and_mask (TREE_TYPE (@0), @1, NEGATE_EXPR, @0,
> + bitop, @2, @3, NULL_TREE, ERROR_MARK,
> + NULL_TREE, NULL_TREE, pmop); }
> + (if (utype)
> + (convert (bit_and (negate (convert:utype { pmop[0]; }))
> + (convert:utype @1)))))))
> +
> /* X % Y is smaller than Y. */
> (for cmp (lt ge)
> (simplify
> --- gcc/testsuite/gcc.dg/tree-ssa/pr86401-1.c.jj 2018-07-04
> 13:36:58.765324864 +0200
> +++ gcc/testsuite/gcc.dg/tree-ssa/pr86401-1.c 2018-07-04 13:40:10.726523960
> +0200
> @@ -0,0 +1,48 @@
> +/* PR tree-optimization/86401 */
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +/* { dg-final { scan-tree-dump-not " \\+ 64" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not "64 - " "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " \\+ 4294967232" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " & 319" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " \\| 4294967168" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " \\^ 4294966912" "optimized" } } */
> +
> +unsigned f1 (unsigned x) { unsigned m = 64; return (m + x) & (m - 1); }
> +unsigned f2 (unsigned x) { return (64 + x) & 63; }
> +unsigned f3 (unsigned x) { unsigned m = 64; return (x + m) & (m - 1); }
> +unsigned f4 (unsigned x) { return (x + 64) & 63; }
> +unsigned f5 (unsigned x) { unsigned m = 64; return (m - x) & (m - 1); }
> +unsigned f6 (unsigned x) { return (64 - x) & 63; }
> +unsigned f7 (unsigned x) { unsigned m = 64; return (x - m) & (m - 1); }
> +unsigned f8 (unsigned x) { return (x - 64) & 63; }
> +unsigned f9 (unsigned x, unsigned y) { unsigned m = 64, n = 256 | (m - 1);
> return ((x & n) + y) & (m - 1); }
> +unsigned f10 (unsigned x, unsigned y) { return ((x & 319) + y) & 63; }
> +unsigned f11 (unsigned x, unsigned y) { unsigned m = 64, n = -128; return
> ((x | n) + y) & (m - 1); }
> +unsigned f12 (unsigned x, unsigned y) { return ((x | -128) + y) & 63; }
> +unsigned f13 (unsigned x, unsigned y) { unsigned m = 64, n = -384; return
> ((x ^ n) + y) & (m - 1); }
> +unsigned f14 (unsigned x, unsigned y) { return ((x ^ -384) + y) & 63; }
> +unsigned f15 (unsigned x, unsigned y) { unsigned m = 64, n = 256 | (m - 1);
> return (y + (x & n)) & (m - 1); }
> +unsigned f16 (unsigned x, unsigned y) { return (y + (x & 319)) & 63; }
> +unsigned f17 (unsigned x, unsigned y) { unsigned m = 64, n = -128; return (y
> + (x | n)) & (m - 1); }
> +unsigned f18 (unsigned x, unsigned y) { return (y + (x | -128)) & 63; }
> +unsigned f19 (unsigned x, unsigned y) { unsigned m = 64, n = -384; return (y
> + (x ^ n)) & (m - 1); }
> +unsigned f20 (unsigned x, unsigned y) { return (y + (x ^ -384)) & 63; }
> +unsigned f21 (unsigned x, unsigned y) { unsigned m = 64, n = 256 | (m - 1);
> return ((x & n) - y) & (m - 1); }
> +unsigned f22 (unsigned x, unsigned y) { return ((x & 319) - y) & 63; }
> +unsigned f23 (unsigned x, unsigned y) { unsigned m = 64, n = -128; return
> ((x | n) - y) & (m - 1); }
> +unsigned f24 (unsigned x, unsigned y) { return ((x | -128) - y) & 63; }
> +unsigned f25 (unsigned x, unsigned y) { unsigned m = 64, n = -384; return
> ((x ^ n) - y) & (m - 1); }
> +unsigned f26 (unsigned x, unsigned y) { return ((x ^ -384) - y) & 63; }
> +unsigned f27 (unsigned x, unsigned y) { unsigned m = 64, n = 256 | (m - 1);
> return (y - (x & n)) & (m - 1); }
> +unsigned f28 (unsigned x, unsigned y) { return (y - (x & 319)) & 63; }
> +unsigned f29 (unsigned x, unsigned y) { unsigned m = 64, n = -128; return (y
> - (x | n)) & (m - 1); }
> +unsigned f30 (unsigned x, unsigned y) { return (y - (x | -128)) & 63; }
> +unsigned f31 (unsigned x, unsigned y) { unsigned m = 64, n = -384; return (y
> - (x ^ n)) & (m - 1); }
> +unsigned f32 (unsigned x, unsigned y) { return (y - (x ^ -384)) & 63; }
> +unsigned f33 (unsigned x) { unsigned m = 64, n = 256 | (m - 1); return (-(x
> & n)) & (m - 1); }
> +unsigned f34 (unsigned x) { return (-(x & 319)) & 63; }
> +unsigned f35 (unsigned x) { unsigned m = 64, n = -128; return (-(x | n)) &
> (m - 1); }
> +unsigned f36 (unsigned x) { return (-(x | -128)) & 63; }
> +unsigned f37 (unsigned x) { unsigned m = 64, n = -384; return (-(x ^ n)) &
> (m - 1); }
> +unsigned f38 (unsigned x) { return (-(x ^ -384)) & 63; }
> --- gcc/testsuite/gcc.dg/tree-ssa/pr86401-2.c.jj 2018-07-04
> 13:47:52.371002780 +0200
> +++ gcc/testsuite/gcc.dg/tree-ssa/pr86401-2.c 2018-07-04 13:48:21.267032753
> +0200
> @@ -0,0 +1,48 @@
> +/* PR tree-optimization/86401 */
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +/* { dg-final { scan-tree-dump-not " \\+ 64" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not "64 - " "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " \\+ -64" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " & 319" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " \\| -128" "optimized" } } */
> +/* { dg-final { scan-tree-dump-not " \\^ -384" "optimized" } } */
> +
> +int f1 (int x) { int m = 64; return (m + x) & (m - 1); }
> +int f2 (int x) { return (64 + x) & 63; }
> +int f3 (int x) { int m = 64; return (x + m) & (m - 1); }
> +int f4 (int x) { return (x + 64) & 63; }
> +int f5 (int x) { int m = 64; return (m - x) & (m - 1); }
> +int f6 (int x) { return (64 - x) & 63; }
> +int f7 (int x) { int m = 64; return (x - m) & (m - 1); }
> +int f8 (int x) { return (x - 64) & 63; }
> +int f9 (int x, int y) { int m = 64, n = 256 | (m - 1); return ((x & n) + y)
> & (m - 1); }
> +int f10 (int x, int y) { return ((x & 319) + y) & 63; }
> +int f11 (int x, int y) { int m = 64, n = -128; return ((x | n) + y) & (m -
> 1); }
> +int f12 (int x, int y) { return ((x | -128) + y) & 63; }
> +int f13 (int x, int y) { int m = 64, n = -384; return ((x ^ n) + y) & (m -
> 1); }
> +int f14 (int x, int y) { return ((x ^ -384) + y) & 63; }
> +int f15 (int x, int y) { int m = 64, n = 256 | (m - 1); return (y + (x & n))
> & (m - 1); }
> +int f16 (int x, int y) { return (y + (x & 319)) & 63; }
> +int f17 (int x, int y) { int m = 64, n = -128; return (y + (x | n)) & (m -
> 1); }
> +int f18 (int x, int y) { return (y + (x | -128)) & 63; }
> +int f19 (int x, int y) { int m = 64, n = -384; return (y + (x ^ n)) & (m -
> 1); }
> +int f20 (int x, int y) { return (y + (x ^ -384)) & 63; }
> +int f21 (int x, int y) { int m = 64, n = 256 | (m - 1); return ((x & n) - y)
> & (m - 1); }
> +int f22 (int x, int y) { return ((x & 319) - y) & 63; }
> +int f23 (int x, int y) { int m = 64, n = -128; return ((x | n) - y) & (m -
> 1); }
> +int f24 (int x, int y) { return ((x | -128) - y) & 63; }
> +int f25 (int x, int y) { int m = 64, n = -384; return ((x ^ n) - y) & (m -
> 1); }
> +int f26 (int x, int y) { return ((x ^ -384) - y) & 63; }
> +int f27 (int x, int y) { int m = 64, n = 256 | (m - 1); return (y - (x & n))
> & (m - 1); }
> +int f28 (int x, int y) { return (y - (x & 319)) & 63; }
> +int f29 (int x, int y) { int m = 64, n = -128; return (y - (x | n)) & (m -
> 1); }
> +int f30 (int x, int y) { return (y - (x | -128)) & 63; }
> +int f31 (int x, int y) { int m = 64, n = -384; return (y - (x ^ n)) & (m -
> 1); }
> +int f32 (int x, int y) { return (y - (x ^ -384)) & 63; }
> +int f33 (int x) { int m = 64, n = 256 | (m - 1); return (-(x & n)) & (m -
> 1); }
> +int f34 (int x) { return (-(x & 319)) & 63; }
> +int f35 (int x) { int m = 64, n = -128; return (-(x | n)) & (m - 1); }
> +int f36 (int x) { return (-(x | -128)) & 63; }
> +int f37 (int x) { int m = 64, n = -384; return (-(x ^ n)) & (m - 1); }
> +int f38 (int x) { return (-(x ^ -384)) & 63; }
> --- gcc/testsuite/c-c++-common/rotate-9.c.jj 2018-07-04 13:53:08.810330994
> +0200
> +++ gcc/testsuite/c-c++-common/rotate-9.c 2018-07-04 13:53:35.481358656
> +0200
> @@ -0,0 +1,19 @@
> +/* PR tree-optimization/86401 */
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fno-ipa-icf -fdump-tree-optimized" } */
> +/* { dg-final { scan-tree-dump-times "r\[<>]\[<>]" 2 "optimized" } } */
> +
> +unsigned int
> +f1 (unsigned int x, unsigned int s)
> +{
> + unsigned int t = s % (__CHAR_BIT__ * __SIZEOF_INT__);
> + return (x << t) | (x >> (((__CHAR_BIT__ * __SIZEOF_INT__) - t) %
> (__CHAR_BIT__ * __SIZEOF_INT__)));
> +}
> +
> +unsigned int
> +f2 (unsigned int x, unsigned int s)
> +{
> + int n = __CHAR_BIT__ * __SIZEOF_INT__;
> + unsigned int t = s % n;
> + return (x << t) | (x >> ((n - t) % n));
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
