2005-09-22 Andreas Krebbel <krebbel1@de.ibm.com>

	* expmed.c (expand_shift): Don't use the target of the rotate as
	target for the first expanded shift insn.
	* testsuite/gcc.dg/20050922-1.c: Testcase added.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@104528 138bc75d-0d04-0410-961f-82ee72b054a4

3 files changed, 49 insertions, 2 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5ba52fe415f..f1a1d8e26ba 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2005-09-22  Andreas Krebbel  <krebbel1@de.ibm.com>
+
+	* expmed.c (expand_shift): Don't use the target of the rotate as
+	target for the first expanded shift insn.
+	* testsuite/gcc.dg/20050922-1.c: Testcase added.
+
 2005-09-21  Zdenek Dvorak  <dvorakz@suse.cz>
 
 	PR tree-optimization/22438
diff --git a/gcc/expmed.c b/gcc/expmed.c
index 27a8b9b1bca..5da9084651f 100644
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -2227,9 +2227,9 @@ expand_shift (enum tree_code code, enum machine_mode mode, rtx shifted,
 	      shifted = force_reg (mode, shifted);
 
 	      temp = expand_shift (left ? LSHIFT_EXPR : RSHIFT_EXPR,
-				   mode, shifted, new_amount, subtarget, 1);
+				   mode, shifted, new_amount, 0, 1);
 	      temp1 = expand_shift (left ? RSHIFT_EXPR : LSHIFT_EXPR,
-				    mode, shifted, other_amount, 0, 1);
+				    mode, shifted, other_amount, subtarget, 1);
 	      return expand_binop (mode, ior_optab, temp, temp1, target,
 				   unsignedp, methods);
 	    }
diff --git a/gcc/testsuite/gcc.dg/20050922-1.c b/gcc/testsuite/gcc.dg/20050922-1.c
new file mode 100644
index 00000000000..93410e53b30
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/20050922-1.c
@@ -0,0 +1,41 @@
+/* This revealed a bug when rotates are expanded into
+   two shifts.  */
+
+/* { dg-do run } */
+/* { dg-options "-O1 -std=c99" } */
+
+#include <stdint.h>
+
+extern void abort (void);
+
+uint32_t
+f (uint32_t *S, int j)
+{
+  uint32_t A, B, k, L[2] = {1234, 5678};
+  int i, m;
+
+  A = B = 0;
+  for (i = 0; i < j; i++)
+    {
+      k = (S[i] + A + B) & 0xffffffffL;
+      A = S[i] =
+      ((k << (3 & 0x1f)) | ((k & 0xffffffff) >> (32 - (3 & 0x1f)))); 
+
+      m = (int) (A + B);
+      k = (L[i] + A + B) & 0xffffffffL;
+      B = L[i] =
+	((k << (m & 0x1f)) | ((k & 0xffffffff) >> (32 - (m & 0x1f))));
+    }
+  return L[0] + L[1];
+}
+
+int
+main ()
+{
+  uint32_t S[2] = {0xffff, 0xffffff};
+
+  if (f (S,2)!= 1392607300)
+    abort();
+
+  return 0;
+}