diff --git a/target/sparc/cpu.h b/target/sparc/cpu.h
index 778aa8e073..ae97c7d9f7 100644
--- a/target/sparc/cpu.h
+++ b/target/sparc/cpu.h
@@ -13,6 +13,39 @@
 
 /*#define EXCP_INTERRUPT 0x100*/
 
+/* Windowed register indexes.  */
+enum {
+    WREG_O0,
+    WREG_O1,
+    WREG_O2,
+    WREG_O3,
+    WREG_O4,
+    WREG_O5,
+    WREG_O6,
+    WREG_O7,
+
+    WREG_L0,
+    WREG_L1,
+    WREG_L2,
+    WREG_L3,
+    WREG_L4,
+    WREG_L5,
+    WREG_L6,
+    WREG_L7,
+
+    WREG_I0,
+    WREG_I1,
+    WREG_I2,
+    WREG_I3,
+    WREG_I4,
+    WREG_I5,
+    WREG_I6,
+    WREG_I7,
+
+    WREG_SP = WREG_O6,
+    WREG_FP = WREG_I6,
+};
+
 /* trap definitions */
 #ifndef TARGET_SPARC64
 #define TT_TFAULT   0x01