From 9b2c6a636d63e58ca3a9ab24193a47267d16bcef Mon Sep 17 00:00:00 2001
From: Jennifer Dupaquier <11723765+jmawet@users.noreply.github.com>
Date: Sat, 1 Feb 2025 23:06:42 +0000
Subject: [PATCH 1/2] complete czero instructions

---
 arch/inst/Zicond/czero.eqz.yaml | 18 +++++++++++++++---
 arch/inst/Zicond/czero.nez.yaml | 16 ++++++++++++++--
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/arch/inst/Zicond/czero.eqz.yaml b/arch/inst/Zicond/czero.eqz.yaml
index 63e65aa53..8afd6fcc5 100644
--- a/arch/inst/Zicond/czero.eqz.yaml
+++ b/arch/inst/Zicond/czero.eqz.yaml
@@ -3,9 +3,12 @@
 $schema: "inst_schema.json#"
 kind: instruction
 name: czero.eqz
-long_name: No synopsis available.
+long_name: Conditional zero, if condition is equal to zero.
 description: |
-  No description available.
+  If rs2 contains the value zero, this instruction writes the value zero to rd. Otherwise, this instruction
+  copies the contents of rs1 to rd.
+  This instruction carries a syntactic dependency from both rs1 and rs2 to rd. Furthermore, if the Zkt
+  extension is implemented, this instruction’s timing is independent of the data values in rs1 and rs2..
 definedBy: Zicond
 assembly: xd, xs1, xs2
 encoding:
@@ -24,12 +27,21 @@ access:
   vu: always
 data_independent_timing: false
 operation(): |
+  XReg input1 = X[rs1];
+  XReg input2 = X[rs2];
+  XReg output = 0;
+
+  if(input2 != 0) {
+    output = input1;
+  }
+
+  X[rd] = output;
 
 sail(): |
   {
     let value = X(rs1);
     let condition = X(rs2);
-    let result : xlenbits = if (condition != zeros()) then zeros()
+    let result : xlenbits = if (condition == zeros()) then zeros()
   						    else value;
     X(rd) = result;
     RETIRE_SUCCESS
diff --git a/arch/inst/Zicond/czero.nez.yaml b/arch/inst/Zicond/czero.nez.yaml
index f3824848a..17338729d 100644
--- a/arch/inst/Zicond/czero.nez.yaml
+++ b/arch/inst/Zicond/czero.nez.yaml
@@ -3,9 +3,12 @@
 $schema: "inst_schema.json#"
 kind: instruction
 name: czero.nez
-long_name: No synopsis available.
+long_name: Conditional zero, if condition is nonzero.
 description: |
-  No description available.
+  If rs2 contains a nonzero value, this instruction writes the value zero to rd. Otherwise, this
+  instruction copies the contents of rs1 to rd.
+  This instruction carries a syntactic dependency from both rs1 and rs2 to rd. Furthermore, if the Zkt
+  extension is implemented, this instruction’s timing is independent of the data values in rs1 and rs2.
 definedBy: Zicond
 assembly: xd, xs1, xs2
 encoding:
@@ -24,6 +27,15 @@ access:
   vu: always
 data_independent_timing: false
 operation(): |
+  XReg input1 = X[rs1];
+  XReg input2 = X[rs2];
+  XReg output = 0;
+
+  if(input2 == 0) {
+    output = input1;
+  }
+
+  X[rd] = output;
 
 sail(): |
   {

From 38633e95c0c18bfbbece0635b2b9d086d8bf5301 Mon Sep 17 00:00:00 2001
From: Jennifer Dupaquier <11723765+jmawet@users.noreply.github.com>
Date: Tue, 4 Feb 2025 03:04:48 +0000
Subject: [PATCH 2/2] syntax and style change

---
 arch/inst/Zicond/czero.eqz.yaml | 12 ++----------
 arch/inst/Zicond/czero.nez.yaml | 10 +---------
 2 files changed, 3 insertions(+), 19 deletions(-)

diff --git a/arch/inst/Zicond/czero.eqz.yaml b/arch/inst/Zicond/czero.eqz.yaml
index 8afd6fcc5..63bdc5a6b 100644
--- a/arch/inst/Zicond/czero.eqz.yaml
+++ b/arch/inst/Zicond/czero.eqz.yaml
@@ -8,7 +8,7 @@ description: |
   If rs2 contains the value zero, this instruction writes the value zero to rd. Otherwise, this instruction
   copies the contents of rs1 to rd.
   This instruction carries a syntactic dependency from both rs1 and rs2 to rd. Furthermore, if the Zkt
-  extension is implemented, this instruction’s timing is independent of the data values in rs1 and rs2..
+  extension is implemented, this instruction’s timing is independent of the data values in rs1 and rs2.
 definedBy: Zicond
 assembly: xd, xs1, xs2
 encoding:
@@ -27,15 +27,7 @@ access:
   vu: always
 data_independent_timing: false
 operation(): |
-  XReg input1 = X[rs1];
-  XReg input2 = X[rs2];
-  XReg output = 0;
-
-  if(input2 != 0) {
-    output = input1;
-  }
-
-  X[rd] = output;
+  X[rd] = (X[rs2] == 0) ? 0 : X[rs1];
 
 sail(): |
   {
diff --git a/arch/inst/Zicond/czero.nez.yaml b/arch/inst/Zicond/czero.nez.yaml
index 17338729d..1e969a605 100644
--- a/arch/inst/Zicond/czero.nez.yaml
+++ b/arch/inst/Zicond/czero.nez.yaml
@@ -27,15 +27,7 @@ access:
   vu: always
 data_independent_timing: false
 operation(): |
-  XReg input1 = X[rs1];
-  XReg input2 = X[rs2];
-  XReg output = 0;
-
-  if(input2 == 0) {
-    output = input1;
-  }
-
-  X[rd] = output;
+  X[rd] = (X[rs2] != 0) ? 0 : X[rs1];
 
 sail(): |
   {