update pseudocode for dsld/dsrd to note that only when Rc=1 is setting
authorLuke Kenneth Casson Leighton <lkcl@lkcl.net>
Wed, 8 Mar 2023 17:19:41 +0000 (17:19 +0000)
committerLuke Kenneth Casson Leighton <lkcl@lkcl.net>
Wed, 8 Mar 2023 17:19:41 +0000 (17:19 +0000)
overflow=1 relevant. for ls003

openpower/isa/svfixedarith.mdwn

index 1b6efd4963b7b802b2a3d9f8488e26c437e3845a..6ce79fb69925bef2faef666c0a251e860ec3e3b0 100644 (file)
@@ -70,7 +70,7 @@ Pseudo-code:
 
 Special Registers Altered:
 
-    None
+    XER.OV
 
 # [DRAFT] Double-width Shift Left Doubleword
 
@@ -86,9 +86,9 @@ Pseudo-code:
     mask <- MASK(0, 63-n)
     RT <- (v[0:63] & mask) | ((RC) & ¬mask)
     RS <- v[0:63] & ¬mask
-    overflow <- 0
+    overflow <- 0             # relevant only when Rc=1
     if RS != [0]*64 then
-        overflow <- 1
+        overflow <- 1         # relevant only when Rc=1
 
 Special Registers Altered:
 
@@ -108,9 +108,9 @@ Pseudo-code:
     mask <- MASK(n, 63)
     RT <- (v[0:63] & mask) | ((RC) & ¬mask)
     RS <- v[0:63] & ¬mask
-    overflow <- 0
+    overflow <- 0             # relevant only when Rc=1
     if RS != [0]*64 then
-        overflow <- 1
+        overflow <- 1         # relevant only when Rc=1
 
 Special Registers Altered: