Added English Language description for stwupx instruction

diff --git a/openpower/isa/pifixedstore.mdwn b/openpower/isa/pifixedstore.mdwn
index 8a45cd96858ca026ec0957baa7f2b50ec6c111c9..2a3160da091b65d090bada2c7a05306ea9c952c3 100644 (file)
--- a/openpower/isa/pifixedstore.mdwn
+++ b/openpower/isa/pifixedstore.mdwn
@@ -147,6 +147,16 @@ Pseudo-code:
     MEM(ea, 4) <- (RS)[XLEN-32:XLEN-1]
     RA <- EA
 
+Description:
+
+    Let the effective address (EA) be the sum (RA)+ (RB).
+    (RS)[32:63] are stored into the word in storage addressed
+    by EA.
+
+    EA is placed into register RA.
+
+    If RA=0, the instruction form is invalid.
+
 Special Registers Altered:
 
     None