From f76968e6d5ab3ca8bd5b64ba0143197c00f59943 Mon Sep 17 00:00:00 2001 From: Richard Guenther Date: Thu, 9 Apr 2009 08:05:43 +0000 Subject: [PATCH] tree-ssa-ccp.c (maybe_fold_stmt_addition): Move non-constant indices into an array reference if possible. 2009-04-09 Richard Guenther * tree-ssa-ccp.c (maybe_fold_stmt_addition): Move non-constant indices into an array reference if possible. * tree-ssa-forwprop.c (tree_ssa_forward_propagate_single_use_vars): Fold POINTER_PLUS_EXPR statements with invariant address. * gcc.dg/tree-ssa/ssa-ccp-25.c: New testcase. * gcc.dg/tree-ssa/ssa-ccp-26.c: Likewise. From-SVN: r145799 --- gcc/ChangeLog | 7 ++++ gcc/testsuite/ChangeLog | 5 +++ gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-25.c | 14 ++++++++ gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-26.c | 11 ++++++ gcc/tree-ssa-ccp.c | 39 ++++++++++++++++++++-- gcc/tree-ssa-forwprop.c | 9 +++++ 6 files changed, 82 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-25.c create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-26.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 581337c9d39..f9ffe707a9b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2009-04-09 Richard Guenther + + * tree-ssa-ccp.c (maybe_fold_stmt_addition): Move non-constant + indices into an array reference if possible. + * tree-ssa-forwprop.c (tree_ssa_forward_propagate_single_use_vars): + Fold POINTER_PLUS_EXPR statements with invariant address. + 2009-04-09 Alan Modra PR target/39634 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 27343277a47..e56170e1cd0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2009-04-09 Richard Guenther + + * gcc.dg/tree-ssa/ssa-ccp-25.c: New testcase. + * gcc.dg/tree-ssa/ssa-ccp-26.c: Likewise. + 2009-04-09 Joseph Myers PR c/39613 diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-25.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-25.c new file mode 100644 index 00000000000..c6e76a2a3fd --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-25.c @@ -0,0 +1,14 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-ccp1 -fdump-tree-forwprop1" } */ + +int a[256]; +int foo(int i) +{ + int *p = &a[0]; + return *(p + i); +} + +/* { dg-final { scan-tree-dump "&a\\\[D\\\." "ccp1" } } */ +/* { dg-final { scan-tree-dump "= a\\\[D\\\." "forwprop1" } } */ +/* { dg-final { cleanup-tree-dump "ccp1" } } */ +/* { dg-final { cleanup-tree-dump "forwprop1" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-26.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-26.c new file mode 100644 index 00000000000..542c4293960 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-26.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-forwprop1" } */ + +int a[256]; +int foo(int i) +{ + return (a + 1)[i]; +} + +/* { dg-final { scan-tree-dump "= a\\\[D\\\." "forwprop1" } } */ +/* { dg-final { cleanup-tree-dump "forwprop1" } } */ diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c index a67850448a7..226fd3dbb27 100644 --- a/gcc/tree-ssa-ccp.c +++ b/gcc/tree-ssa-ccp.c @@ -2114,14 +2114,47 @@ maybe_fold_stmt_addition (tree res_type, tree op0, tree op1) tree ptd_type; tree t; - /* It had better be a constant. */ - if (TREE_CODE (op1) != INTEGER_CST) - return NULL_TREE; /* The first operand should be an ADDR_EXPR. */ if (TREE_CODE (op0) != ADDR_EXPR) return NULL_TREE; op0 = TREE_OPERAND (op0, 0); + /* It had better be a constant. */ + if (TREE_CODE (op1) != INTEGER_CST) + { + /* Or op0 should now be A[0] and the non-constant offset defined + via a multiplication by the array element size. */ + if (TREE_CODE (op0) == ARRAY_REF + && integer_zerop (TREE_OPERAND (op0, 1)) + && TREE_CODE (op1) == SSA_NAME + && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (op0)), 1)) + { + gimple offset_def = SSA_NAME_DEF_STMT (op1); + if (!is_gimple_assign (offset_def)) + return NULL_TREE; + + if (gimple_assign_rhs_code (offset_def) == MULT_EXPR + && TREE_CODE (gimple_assign_rhs2 (offset_def)) == INTEGER_CST + && tree_int_cst_equal (gimple_assign_rhs2 (offset_def), + TYPE_SIZE_UNIT (TREE_TYPE (op0)))) + return build1 (ADDR_EXPR, res_type, + build4 (ARRAY_REF, TREE_TYPE (op0), + TREE_OPERAND (op0, 0), + gimple_assign_rhs1 (offset_def), + TREE_OPERAND (op0, 2), + TREE_OPERAND (op0, 3))); + else if (integer_onep (TYPE_SIZE_UNIT (TREE_TYPE (op0))) + && gimple_assign_rhs_code (offset_def) != MULT_EXPR) + return build1 (ADDR_EXPR, res_type, + build4 (ARRAY_REF, TREE_TYPE (op0), + TREE_OPERAND (op0, 0), + op1, + TREE_OPERAND (op0, 2), + TREE_OPERAND (op0, 3))); + } + return NULL_TREE; + } + /* If the first operand is an ARRAY_REF, expand it so that we can fold the offset into it. */ while (TREE_CODE (op0) == ARRAY_REF) diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index ff6bda0b1de..f75e0afa73f 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -1256,6 +1256,15 @@ tree_ssa_forward_propagate_single_use_vars (void) else gsi_next (&gsi); } + else if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR + && is_gimple_min_invariant (rhs)) + { + /* Make sure to fold &a[0] + off_1 here. */ + fold_stmt_inplace (stmt); + update_stmt (stmt); + if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) + gsi_next (&gsi); + } else if ((gimple_assign_rhs_code (stmt) == BIT_NOT_EXPR || gimple_assign_rhs_code (stmt) == NEGATE_EXPR) && TREE_CODE (rhs) == SSA_NAME) -- 2.30.2