PR rtl-optimization/32283

	* tree-ssa-loop-niter.c (scev_probably_wraps_p): Use type of the base
	of the induction variable to decide whether it may wrap.
	* tree-ssa-loop-ivopts.c (rewrite_use_compare): Emit the initialization
	of the bound before the loop.
	* simplify-rtx.c (simplify_binary_operation_1): Add two simplifications
	regarding AND.
	(simplify_plus_minus): Only fail if no simplification is possible.
	* loop-iv.c (simple_rhs_p): Consider reg + reg and reg << cst simple.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@142035 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 19 insertions, 6 deletions

diff --git a/gcc/loop-iv.c b/gcc/loop-iv.c
index 2523963f36d..3723dbd463a 100644
--- a/gcc/loop-iv.c
+++ b/gcc/loop-iv.c
@@ -1337,13 +1337,26 @@ simple_rhs_p (rtx rhs)
     case MINUS:
       op0 = XEXP (rhs, 0);
       op1 = XEXP (rhs, 1);
-      /* Allow reg + const sets only.  */
-      if (REG_P (op0) && !HARD_REGISTER_P (op0) && CONSTANT_P (op1))
-	return true;
-      if (REG_P (op1) && !HARD_REGISTER_P (op1) && CONSTANT_P (op0))
-	return true;
+      /* Allow reg + const and reg + reg.  */
+      if (!(REG_P (op0) && !HARD_REGISTER_P (op0))
+	  && !CONSTANT_P (op0))
+	return false;
+      if (!(REG_P (op1) && !HARD_REGISTER_P (op1))
+	  && !CONSTANT_P (op1))
+	return false;
 
-      return false;
+      return true;
+
+    case ASHIFT:
+      op0 = XEXP (rhs, 0);
+      op1 = XEXP (rhs, 1);
+      /* Allow reg << const.  */
+      if (!(REG_P (op0) && !HARD_REGISTER_P (op0)))
+	return false;
+      if (!CONSTANT_P (op1))
+	return false;
+
+      return true;
 
     default:
       return false;