PR tree-optimization/43236

        * tree-loop-distribution.c (generate_memset_zero): Fix off-by-one
        error in calculation of base address in reverse iteration case.
        (generate_builtin): Take number of latch executions if the statement
        is in the latch.

        * gcc.c-torture/execute/pr43236.c: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@157339 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 32e2eab..55a998c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2010-03-10  Alexander Monakov  <amonakov@ispras.ru>
+
+       PR tree-optimization/43236
+       * tree-loop-distribution.c (generate_memset_zero): Fix off-by-one
+       error in calculation of base address in reverse iteration case.
+       (generate_builtin): Take number of latch executions if the statement
+       is in the latch.
+
 2010-03-10  Andrey Belevantsev  <abel@ispras.ru>
 
        PR middle-end/42859

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index bf4ccf7..edb88dd 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-03-10  Alexander Monakov  <amonakov@ispras.ru>
+
+       PR tree-optimization/43236
+       * gcc.c-torture/execute/pr43236.c: New test.
+
 2010-03-10  Andrey Belevantsev  <abel@ispras.ru>
 
        PR middle-end/42859

diff --git a/gcc/testsuite/gcc.c-torture/execute/pr43236.c b/gcc/testsuite/gcc.c-torture/execute/pr43236.c
new file mode 100644 (file)
index 0000000..0401c88
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr43236.c
@@ -0,0 +1,32 @@
+/* { dg-options "-ftree-loop-distribution" } */
+extern void abort(void);
+extern void *memset(void *s, int c, __SIZE_TYPE__ n);
+extern int memcmp(const void *s1, const void *s2, __SIZE_TYPE__ n);
+/*extern int printf(const char *format, ...);*/
+
+int main()
+{
+  char A[30], B[30], C[30];
+  int i;
+
+  /* prepare arrays */
+  memset(A, 1, 30);
+  memset(B, 1, 30);
+
+  for (i = 20; i-- > 10;) {
+    A[i] = 0;
+    B[i] = 0;
+  }
+
+  /* expected result */
+  memset(C, 1, 30);
+  memset(C + 10, 0, 10);
+
+  /* show result */
+/*  for (i = 0; i < 30; i++)
+    printf("%d %d %d\n", A[i], B[i], C[i]); */
+
+  /* compare results */
+  if (memcmp(A, C, 30) || memcmp(B, C, 30)) abort();
+  return 0;
+}

diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index 920ab8c..74120c6 100644 (file)
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -285,6 +285,8 @@ generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
       addr_base = fold_convert_loc (loc, sizetype, addr_base);
       addr_base = size_binop_loc (loc, MINUS_EXPR, addr_base,
                                  fold_convert_loc (loc, sizetype, nb_bytes));
+      addr_base = size_binop_loc (loc, PLUS_EXPR, addr_base,
+                                 TYPE_SIZE_UNIT (TREE_TYPE (op0)));
       addr_base = fold_build2_loc (loc, POINTER_PLUS_EXPR,
                                   TREE_TYPE (DR_BASE_ADDRESS (dr)),
                                   DR_BASE_ADDRESS (dr), addr_base);
@@ -389,6 +391,8 @@ generate_builtin (struct loop *loop, bitmap partition, bool copy_p)
                goto end;
 
              write = stmt;
+             if (bb == loop->latch)
+               nb_iter = number_of_latch_executions (loop);
            }
        }
     }