diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6d083c07874..c81681cc796 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2005-05-18  Devang Patel  <dpatel@apple.com>
+
+	* config/rs6000/rs6000.md (insvsi_internal1): Subtract shift from
+	the mask end.
+	
 2005-05-18  Richard Henderson  <rth@redhat.com>
 
         * tree-ssa-forwprop.c (cfg_changed): New.
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index b53792c32ae..2c0b0491abe 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -3014,7 +3014,7 @@
   int size = INTVAL (operands[1]) & 31;
 
   operands[4] = GEN_INT (shift - start - size);
-  operands[1] = GEN_INT (start + size - 1);
+  operands[1] = GEN_INT (start + size - 1 - shift);
   return \"{rlimi|rlwimi} %0,%3,%h4,%h2,%h1\";
 }"
   [(set_attr "type" "insert_word")])
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 74b37015dc0..78580bc0933 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2005-05-18  Devang Patel  <dpatel@apple.com>
+
+	* g++.dg/opt/20050511-1.C: New test.
+	
 2005-05-18  Thomas Koenig  <Thomas.Koenig@online.de>
 
 	PR libfortran/21127
diff --git a/gcc/testsuite/g++.dg/opt/20050511-1.C b/gcc/testsuite/g++.dg/opt/20050511-1.C
new file mode 100644
index 00000000000..e04b2b863e9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/20050511-1.C
@@ -0,0 +1,64 @@
+/* { dg-do run } */
+/* { dg-options "-O3" { target powerpc*-*-* } } */
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef signed short SINT16 ;
+typedef unsigned long UINT32 ;
+typedef unsigned int UINT ;
+
+class A
+{
+public:
+    union   
+    {
+      SINT16 xy[2];
+      UINT32 abXY;
+    };
+  bool operator==(const A& other) const {return abXY == other.abXY;}
+  bool operator!=(const A& other) const {return abXY != other.abXY;}
+};
+
+template <int size> struct pArray { unsigned char u08[16*(((size*1)+15)/16)] __attribute__ ((aligned(16))); };
+
+struct B
+{
+  union {
+    A mvL[2];
+    pArray<1> xyz;
+  };
+} ;
+
+typedef struct
+{
+  UINT w;
+  B b;
+
+}C;
+
+
+UINT32 bar (const C * sPtr)
+{
+  UINT w = sPtr->w;
+  A a;
+
+  a.xy[0] = sPtr->b.mvL[w].xy[0]<<2;
+  a.xy[1] = sPtr->b.mvL[w].xy[1]<<2;
+
+  if (a.xy[0] != ((SINT16) 0xffff << 2))
+	abort ();
+}
+
+int main()
+{
+	A a;
+	C c;
+	a.xy[0] = 0xffff;
+	a.xy[1] = 0xffff;
+	c.w=0;
+	c.b.mvL[0].xy[0] = a.xy[0];
+	c.b.mvL[0].xy[1] = a.xy[1];
+
+	bar (&c);
+}
+