diff options
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/tailrecursion-7.c | 40 | ||||
| -rw-r--r-- | gcc/tree-tailcall.c | 63 |
4 files changed, 94 insertions, 20 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1edae2f1107..141063e25ad 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2010-09-05 Giuseppe Scrivano <gscrivano@gnu.org> + + * tree-tailcall.c (process_assignment): Handle NEGATE_EXPR and + MINUS_EXPR. + 2010-09-05 Mark Mitchell <mark@codesourcery.com> * doc/invoke.texi: Document -Wdouble-promotion. @@ -19,7 +24,7 @@ * config/sh/sh.c (sh_option_override): Make static. Adjust comments. Declare. - (sh_function_value_regno_p): Likewise. + (sh_function_value_regno_p): Likewise. (sh_register_move_cost): Modify the arguments, make static. Adjust comments. Declare. (TARGET_OPTION_OVERRIDE, TARGET_REGISTER_MOVE_COST diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 316811e0f21..d72be505c1c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2010-09-05 Giuseppe Scrivano <gscrivano@gnu.org> + + * gcc.dg/tree-ssa/tailrecursion-7.c: New file. + 2010-09-05 Mark Mitchell <mark@codesourcery.com> * gcc.dg/Wdouble-promotion.c: New. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/tailrecursion-7.c b/gcc/testsuite/gcc.dg/tree-ssa/tailrecursion-7.c new file mode 100644 index 00000000000..875a6aa7887 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/tailrecursion-7.c @@ -0,0 +1,40 @@ +/* { dg-do run } */ +/* { dg-options "-O1 -foptimize-sibling-calls -fdump-tree-optimized" } */ + +extern void abort (void); +extern void exit (int); + +int foo (int n) +{ + return n == 0 ? 1 : n * (n - foo (n - 1)); +} + +int bar (int n) +{ + return n == 0 ? 1 : n * (- bar (n - 1)); +} + +int baz (int n, int m) +{ + return n == 0 ? 100 : (baz (n - 1, m) - m); +} + +int main (void) +{ + if (foo (6) != 726) + abort (); + + if (bar (7) != -5040) + abort (); + + if (baz (10, 5) != 50) + abort (); + + exit (0); +} + +/* { dg-final { scan-tree-dump-times "\\mfoo\\M" 4 "optimized"} } */ +/* { dg-final { scan-tree-dump-times "\\mbar\\M" 4 "optimized"} } */ +/* { dg-final { scan-tree-dump-times "\\mbaz\\M" 4 "optimized"} } */ + +/* { dg-final { cleanup-tree-dump "optimized" } } */ diff --git a/gcc/tree-tailcall.c b/gcc/tree-tailcall.c index 65eaa40cedb..71a273f6fe5 100644 --- a/gcc/tree-tailcall.c +++ b/gcc/tree-tailcall.c @@ -252,7 +252,7 @@ static bool process_assignment (gimple stmt, gimple_stmt_iterator call, tree *m, tree *a, tree *ass_var) { - tree op0, op1, non_ass_var; + tree op0, op1 = NULL_TREE, non_ass_var = NULL_TREE; tree dest = gimple_assign_lhs (stmt); enum tree_code code = gimple_assign_rhs_code (stmt); enum gimple_rhs_class rhs_class = get_gimple_rhs_class (code); @@ -278,8 +278,20 @@ process_assignment (gimple stmt, gimple_stmt_iterator call, tree *m, return true; } - if (rhs_class != GIMPLE_BINARY_RHS) - return false; + switch (rhs_class) + { + case GIMPLE_BINARY_RHS: + op1 = gimple_assign_rhs2 (stmt); + + /* Fall through. */ + + case GIMPLE_UNARY_RHS: + op0 = gimple_assign_rhs1 (stmt); + break; + + default: + return false; + } /* Accumulator optimizations will reverse the order of operations. We can only do that for floating-point types if we're assuming @@ -288,20 +300,9 @@ process_assignment (gimple stmt, gimple_stmt_iterator call, tree *m, if (FLOAT_TYPE_P (TREE_TYPE (DECL_RESULT (current_function_decl)))) return false; - /* We only handle the code like - - x = call (); - y = m * x; - z = y + a; - return z; - - TODO -- Extend it for cases where the linear transformation of the output - is expressed in a more complicated way. */ - - op0 = gimple_assign_rhs1 (stmt); - op1 = gimple_assign_rhs2 (stmt); - - if (op0 == *ass_var + if (rhs_class == GIMPLE_UNARY_RHS) + ; + else if (op0 == *ass_var && (non_ass_var = independent_of_stmt_p (op1, stmt, call))) ; else if (op1 == *ass_var @@ -322,8 +323,32 @@ process_assignment (gimple stmt, gimple_stmt_iterator call, tree *m, *ass_var = dest; return true; - /* TODO -- Handle other codes (NEGATE_EXPR, MINUS_EXPR, - POINTER_PLUS_EXPR). */ + case NEGATE_EXPR: + if (FLOAT_TYPE_P (TREE_TYPE (op0))) + *m = build_real (TREE_TYPE (op0), dconstm1); + else + *m = build_int_cst (TREE_TYPE (op0), -1); + + *ass_var = dest; + return true; + + case MINUS_EXPR: + if (*ass_var == op0) + *a = fold_build1 (NEGATE_EXPR, TREE_TYPE (non_ass_var), non_ass_var); + else + { + if (FLOAT_TYPE_P (TREE_TYPE (non_ass_var))) + *m = build_real (TREE_TYPE (non_ass_var), dconstm1); + else + *m = build_int_cst (TREE_TYPE (non_ass_var), -1); + + *a = fold_build1 (NEGATE_EXPR, TREE_TYPE (non_ass_var), non_ass_var); + } + + *ass_var = dest; + return true; + + /* TODO -- Handle POINTER_PLUS_EXPR. */ default: return false; |