PR rtl-optimization/15139

	* combine.c: Include params.h.
	(count_rtxs): New function.
	(record_value_for_reg): If replace_rtx would replace at least
	2 occurrences of REG in VALUE and TEM is really large, replace REG with
	(clobber (const_int 0)) instead of TEM.
	* params.def (PARAM_MAX_LAST_VALUE_RTL): New.
	* params.h (MAX_LAST_VALUE_RTL): New.
	* Makefile.in (combine.o): Depend on $(PARAMS_H).
	* doc/invoke.texi (--param max-last-value-rtl=N): Document.

	* gcc.dg/20050111-2.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@93892 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 21 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.dg/20050111-2.c b/gcc/testsuite/gcc.dg/20050111-2.c
new file mode 100644
index 00000000000..17e59ce968c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/20050111-2.c
@@ -0,0 +1,21 @@
+/* PR rtl-optimization/15139 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -funroll-loops" } */
+
+void
+foo (double **a, double **z)
+{
+  long int i, j;
+  double d = -1.0;
+
+  for (i = 0; i < 6; i++)
+    for (j = 0; j < 5; j++)
+      d = z[i][j] > d ? z[i][j] : d;
+
+  for (i = 0; i < 6; i++)
+    for (j = 0; j < 5; j++)
+      z[i][j] /= d;
+
+  for (i = 0; i < 5; i++)
+    a[i][j] = z[i][j];
+}