Fix PR middle-end/90796

        PR middle-end/90796
        * gimple-loop-jam.c (any_access_function_variant_p): New function.
        (adjust_unroll_factor): Use it to constrain safety, new parameter.
        (tree_loop_unroll_and_jam): Adjust call and profitable unroll factor.

testsuite/
        * gcc.dg/unroll-and-jam.c: Add three invalid and one valid case.

git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@277287 138bc75d-0d04-0410-961f-82ee72b054a4

2 files changed, 23 insertions, 4 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9827b38387d..9caf60787d4 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-10-22  Michael Matz  <matz@suse.de>
+
+	PR middle-end/90796
+	* gcc.dg/unroll-and-jam.c: Add three invalid and one valid case.
+
 2019-10-22  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/92173
diff --git a/gcc/testsuite/gcc.dg/unroll-and-jam.c b/gcc/testsuite/gcc.dg/unroll-and-jam.c
index 70910d318cb..bcfe1bda9b0 100644
--- a/gcc/testsuite/gcc.dg/unroll-and-jam.c
+++ b/gcc/testsuite/gcc.dg/unroll-and-jam.c
@@ -31,10 +31,10 @@ void checkb(void)
   //printf("  %d\n", sum);
 }
 
+unsigned i, j;
 #define TEST(name, body, test) \
 static void __attribute__((noinline,noclone)) name (unsigned long n, unsigned long m) \
 { \
-  unsigned long i, j; \
   for (i = 1; i < m; i++) { \
       for (j = 1; j < n; j++) { \
 	  body; \
@@ -58,9 +58,14 @@ TEST(foo3, aa[i+1][j-1]=aa[i][j] * aa[i][j] / 2, checkaa()) //notok, -1,1
 TEST(foo4, aa[i][j] = aa[i-1][j+1] * aa[i-1][j+1] / 2, checkaa()) //notok, -1,1
 TEST(foo5, aa[i][j] = aa[i+1][j+1] * aa[i+1][j+1] / 2, checkaa()) //ok, 1,1
 TEST(foo6, aa[i][j] = aa[i+1][j] * aa[i+1][j] / 2, checkaa()) //ok, -1,0
+TEST(foo61, aa[i][0] = aa[i+1][0] * aa[i+1][0] / 2, checkaa()) //notok, -1,0
+TEST(foo62, aa[i][j/2] = aa[i+1][j/2] * aa[i+1][j/2] / 2, checkaa()) //notok, not affine
+TEST(foo63, aa[i][j%2] = aa[i+1][j%2] * aa[i+1][j%2] / 2, checkaa()) //notok, not affine
 TEST(foo7, aa[i+1][j] = aa[i][j] * aa[i][j] / 2, checkaa()) //ok, 1,0
 TEST(foo9, b[j] = 3*b[j+1] + 1, checkb()) //notok, 0,-1
 TEST(foo10, b[j] = 3*b[j] + 1, checkb()) //ok, 0,0
+extern int f;
+TEST(foo11, f = b[i-1] = 1 + 3* b[i+1], checkb()) //ok, 2,0 but must reduce unroll factor to 2, (it would be incorrect with unroll-by-3, which the profitability would suggest)
 
 /* foo8 should work as well, but currently doesn't because the distance
    vectors we compute are too pessimistic.  We compute
@@ -68,6 +73,7 @@ TEST(foo10, b[j] = 3*b[j] + 1, checkb()) //ok, 0,0
    and the last one causes us to lose.  */
 TEST(foo8, b[j+1] = 3*b[j] + 1, checkb()) //ok, 0,1
 
+int f;
 unsigned int a[1024];
 unsigned int b[1024];
 unsigned int aa[16][1024];
@@ -88,10 +94,12 @@ void init(void)
     printf(" %s\n", #name); \
     init();for(i=0;i<4;i++)name##noopt(32,8); checka = checksum; \
     init();for(i=0;i<4;i++)name(32,8); \
+    if (checka != checksum) fail = 1; \
     printf("%sok %s\n", checka != checksum ? "NOT " : "", #name);
 
 int main()
 {
+  int fail = 0;
   int i;
   unsigned checka;
   RUN(foo1);
@@ -100,12 +108,18 @@ int main()
   RUN(foo4);
   RUN(foo5);
   RUN(foo6);
+  RUN(foo61);
+  RUN(foo62);
+  RUN(foo63);
   RUN(foo7);
   RUN(foo8);
   RUN(foo9);
   RUN(foo10);
-  return 0;
+  RUN(foo11);
+  if (fail)
+    __builtin_abort();
+  return fail;
 }
 
-/* Five loops should be unroll-jammed (actually six, but see above).  */
-/* { dg-final { scan-tree-dump-times "applying unroll and jam" 5 "unrolljam" } } */
+/* Six loops should be unroll-jammed (actually seven, but see above).  */
+/* { dg-final { scan-tree-dump-times "applying unroll and jam" 6 "unrolljam" } } */