From: lkcl <lkcl@web>
Date: Sat, 4 Jun 2022 23:39:09 +0000 (+0100)
Subject: (no commit message)
X-Git-Tag: opf_rfc_ls005_v1~1959
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=c9e7d78cfd65d7e8649aaf9094ad4616ca596b49;p=libreriscv.git

---

diff --git a/openpower/sv/fclass.mdwn b/openpower/sv/fclass.mdwn
index aad1974b8..1e26bc5cd 100644
--- a/openpower/sv/fclass.mdwn
+++ b/openpower/sv/fclass.mdwn
@@ -7,13 +7,13 @@ based on xvtstdcsp v3.0B p768 the instruction performs analysis of the FP number
 unlike xvtstdcsp the result is stored in a Condition Register specified by BF.
 this allows it to be used as a predicate mask.  setb may be used to create the equivalent of xvtstdcsp if desired.
 
-| 0.5| 6.8 |9.10|11.15| 16.20 | 21...30 |31|  name   | Form    |
-| -- | --- | -- | --- | ----- | ------- |--| ------- | ------  |
-| PO | BF  | dx | FRA | dc    | XO      |dm| fptstsp | XX2-Form|
+| 0.5| 6.8 |9..15 | 16.20 | 21...30 |31|  name   | Form    |
+| -- | --- | --   | ----- | ------- |--| ------- | ------  |
+| PO | BF  | DCMX | FRB   | XO      |dm| fptstsp | XX2-Form|
 
 ```
-DCMX <- dc || dm || dx
-src  <- (FRA)[32:63]
+dcmx <- DCMX || dm
+src  <- (FRB)[32:63]
 sign  <- src[0]
 exponent  <- src[1:8]
 fraction  <- src[9:31]
@@ -21,21 +21,22 @@ class.Infinity  <- (exponent = 0xFF) & (fraction = 0)
 class.NaN  <- (exponent = 0xFF) & (fraction != 0)
 class.Zero  <- (exponent = 0x00) & (fraction = 0)
 class.Denormal  <- (exponent = 0x00) & (fraction != 0)
-CR{BF} <- ((DCMX[0] & class.NaN & !sign)  |
-           (DCMX[1] & class.NaN & sign))  ||
-          ((DCMX[6] & class.Denormal & !sign) |
-           (DCMX[7] & class.Denormal & sign)) ||
-          ((DCMX[2] & class.Infinity & !sign) |
+CR{BF} <- ((dcmx[0] & class.NaN & !sign)  |
+           (dcmx[1] & class.NaN & sign))  ||
+          ((dcmx[6] & class.Denormal & !sign) |
+           (dcmx[7] & class.Denormal & sign)) ||
+          ((dcmx[2] & class.Infinity & !sign) |
            (DCMX[3] & class.Infinity & sign)) ||
-          ((DCMX[4] & class.Zero & !sign) |
-           (DCMX[5] & class.Zero & sign))
+          ((dcmx[4] & class.Zero & !sign) |
+           (dcmx[5] & class.Zero & sign))
 ```
 
 64 bit variant fptstdp is as follows:
 
 ```
-sign <- src.bit[0]
-exponent <- src.bit[1:11]
-fraction <- src.bit[12:63]
+src  <- (FRB)
+sign <- src[0]
+exponent <- src[1:11]
+fraction <- src[12:63]
       exponent & 7FF
 ```