Stop using term executable vector (#516)

Fixes #510

Co-authored-by: Andres Amaya Garcia <[email protected]>

src/csv/CHERI_CSR.csv

@@ -1,4 +1,4 @@
-"CLEN CSR","Address","Alias","Mode","Permissions","Reset Value","Action on XLEN write","Action on CLEN write","Executable Vector","Data Pointer","Unseal On Execution","Store full metadata","Prerequisites","Description","","","","","","","","","","","","","","","","","","","","",""
+"CLEN CSR","Address","Alias","Mode","Permissions","Reset Value","Action on XLEN write","Action on CLEN write","Code Pointer","Data Pointer","Unseal On Execution","Store full metadata","Prerequisites","Description","","","","","","","","","","","","","","","","","","","","",""
 "dpcc","0x7b1","dpc","D","DRW","tag=0, otherwise undefined","Apply <<section_invalid_addr_conv>>.
 Always update the CSR with <<SCADDR>> even if the address didn't change.","Apply <<section_invalid_addr_conv>> and update the CSR with the result if the address changed,
 direct write if address didn't change","✔","","✔","","Sdext","Debug Program Counter Capability","","","","","","","","","","","","","","","","","","","","",""

src/riscv-integration.adoc

@@ -457,7 +457,7 @@ ISAs must support both {cheri_base_ext_name} and {cheri_default_ext_name}.
 ==== Machine Trap Vector Base Address Register (mtvec)
 
 The <<mtvec>> register is as defined in cite:[riscv-priv-spec]. It is an
-MXLEN-bit register used as the executable vector jumped to when taking traps
+MXLEN-bit register used as the code pointer jumped to when taking traps
 into machine mode. It is extended into <<mtvecc>>.
 
 
@@ -469,7 +469,7 @@ include::img/mtvecreg.edn[]
 
 The <<mtvecc>> register is a renamed extension of <<mtvec>> that holds a
 capability.  Its reset value is the <<infinite-cap>> capability. The capability
-represents an executable vector.
+represents a code pointer.
 
 .Machine-mode trap-vector base-capability register
 include::img/mtveccreg.edn[]
@@ -877,7 +877,7 @@ hold capabilities or with other new functions. <<asr_perm>> in the <<pcc>> is ty
 ==== Supervisor Trap Vector Base Address Register (stvec)
 
 The <<stvec>> register is as defined in cite:[riscv-priv-spec]. It is an
-SXLEN-bit register used as the executable vector jumped to when taking traps
+SXLEN-bit register used as the code pointer jumped to when taking traps
 into supervisor mode. It is extended into <<stvecc>>.
 
 .Supervisor trap-vector base-address register

src/scripts/generate_tables.py

@@ -592,7 +592,7 @@ def check(self,row):
         return row[self.header.index("CLEN CSR")] != ""
 
 class csr_exevectors(table):
-    cols = ["CLEN CSR", "Executable Vector", "Data Pointer", "Unseal On Execution"]
+    cols = ["CLEN CSR", "Code Pointer", "Data Pointer", "Unseal On Execution"]
     indices = []
 
     def __init__(self, filename, header):
@@ -614,7 +614,7 @@ def update(self, row):
             self.file.write(outStr+'\n')
 
     def check(self,row):
-        return row[self.header.index("Executable Vector")] == "✔" or \
+        return row[self.header.index("Code Pointer")] == "✔" or \
             row[self.header.index("Unseal On Execution")] == "✔" or \
             row[self.header.index("Data Pointer")] == "✔"
 

src/tables.adoc

@@ -103,17 +103,19 @@ NOTE: Implementations which allow misa.C to be writable need to legalize *Xepcc*
  on _reading_ if the misa.C value has changed since the value was written as this
  can cause the read value of bit [1] to change state.
 
-.CLEN-wide CSRs storing executable vectors or data pointers
+.CLEN-wide CSRs storing code pointers or data pointers
 [#CSR_exevectors]
 [width="100%",options=header,cols="1,1,1,1"]
 |==============================================================================
 include::generated/csr_exevectors_table_body.adoc[]
 |==============================================================================
 
-Some CSRs store executable vectors or data pointers as shown in xref:CSR_exevectors[xrefstyle=short].
-These CSRs do not need to store the full width address on RV64.
-If they store fewer address bits then writes are subject to the invalid address
-check in <<section_invalid_addr_conv>>.
+Some CSRs store code pointers or data pointers as shown in xref:CSR_exevectors[xrefstyle=short].
+These are WARL CSRs that do not need to store full 64-bit addresses on RV64, and so need not be capable
+of holding all possible invalid addresses. Prior to writing an invalid address to these CSRs,
+the address must be converted to another invalid address that the CSR is capable of holding.
+CSRs that store fewer address bits are also subject to the invalid address
+check in <<section_invalid_addr_conv>> on writing.
 
 .CLEN-wide CSRs which store all CLEN+1 bits
 [#CSR_metadata]