simplify-rtx.c (simplifi_binary_operation): If DIV has narrower mode than op0, only...

	* simplify-rtx.c (simplifi_binary_operation) [DIV]: If DIV has
	narrower mode than op0, only return the bits in DIV's mode.

	* gcc.c-torture/compile/20011219-2.c: New test.

From-SVN: r48199

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f1634cc47449d6a4c030a2d52949e2558eb7707b..0f25ad6dec239389f2ac467ca8740ee095323e53 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2001-12-20  Jakub Jelinek  <jakub@redhat.com>
+
+       * simplify-rtx.c (simplifi_binary_operation) [DIV]: If DIV has
+       narrower mode than op0, only return the bits in DIV's mode.
+
 2001-12-20  Jakub Jelinek  <jakub@redhat.com>
 
        * combine.c (distribute_notes): Avoid adding REG_LABEL notes

diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 122768e41227be715df07cfb85f89d5361570652..2b25d9c799a69742ff5c6a0c53343f8a930eb0dc 100644 (file)
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -1412,7 +1412,10 @@ simplify_binary_operation (code, mode, op0, op1)
 
        case DIV:
          if (trueop1 == CONST1_RTX (mode))
-           return op0;
+           {
+             rtx x = gen_lowpart_common (mode, op0);
+             return x ? x : op0;
+           }
 
          /* In IEEE floating point, 0/x is not always 0.  */
          if ((TARGET_FLOAT_FORMAT != IEEE_FLOAT_FORMAT

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index de0cdf8810a3bba9c51d72511abef4947a49c2df..aaee1d55371cc1475fc08a481a19c478cbf3a1bb 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,7 @@
 2001-12-20  Jakub Jelinek  <jakub@redhat.com>
 
+       * gcc.c-torture/compile/20011219-2.c: New test.
+
        * gcc.c-torture/execute/20011219-1.c: New test.
 
 2001-12-19  David Billinghurst <David.Billinghurst@riotinto.com>

diff --git a/gcc/testsuite/gcc.c-torture/compile/20011219-2.c b/gcc/testsuite/gcc.c-torture/compile/20011219-2.c
new file mode 100644 (file)
index 0000000..2ad7eb1
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/20011219-2.c
@@ -0,0 +1,20 @@
+/* This testcase failed on Alpha at -O2 when simplifying conditional
+   expressions.  */
+
+struct S {
+  unsigned long a;
+  double b, c;
+};
+
+extern double bar (double, double);
+
+int
+foo (unsigned long x, unsigned int y, struct S *z)
+{
+  unsigned int a = z->a;
+  int b = y / z->a > 1 ? y / z->a : 1;
+
+  a = y / b < z->a ? y / b : z->a;
+  z->c = z->b * bar ((double) a, (double) x);
+  return 0;
+}