From 6263041aa1fd3b04eb8288860f1d5a3ce4925184 Mon Sep 17 00:00:00 2001
From: Akilan <me@akilan.io>
Date: Mon, 23 Feb 2026 12:26:03 +0000
Subject: [PATCH] fixed removing areas where delta values were used

---
 CHERICC_Fat.bsv | 52 ++++++++++++++++++++++++-------------------------
 CHERICap.bsv    |  3 +--
 2 files changed, 26 insertions(+), 29 deletions(-)

diff --git a/CHERICC_Fat.bsv b/CHERICC_Fat.bsv
index b186450..38840fb 100644
--- a/CHERICC_Fat.bsv
+++ b/CHERICC_Fat.bsv
@@ -145,7 +145,7 @@ typedef SizeOf#(Perms) PermsW;
 typedef TSub#(CapW, TAdd#( CapAddrW
                          , TAdd#( OTypeW
                                     , TAdd#( CBoundsW
-                                       , TAdd#(PermsW, FlagsW)))))) ResW;
+                                       , TAdd#(PermsW, FlagsW))))) ResW;
 // The full capability structure, including the "tag" bit.
 typedef struct {
   Bool         isCapability;
@@ -1548,31 +1548,29 @@ typedef struct {
   Bit#(VA_Width)     address;
   Bool         validAddress;
 } CapTrim deriving(Bits, Eq, FShow);
-// function CapTrim  trimCap(CapMem cm);
-//   CapabilityInMemory cap = unpack(cm);
-//   Bit#(TSub#(CapAddrW,VA_Width)) addr_upper = truncateLSB(cap.address);
-//   return CapTrim{perms: cap.perms,
-//                  flags: cap.flags,
-//                  delta: cap.delta,
-//                  bounds: cap.bounds,  
-//                  address: truncate(cap.address),
-//                  validAddress: (addr_upper==signExtend(cap.address[valueOf(VA_Width)-1]))
-//   };
-// endfunction
-// function CapMem untrimCap(CapTrim ct);
-//   // Encode an invalid address as the bit above the last valid bit being different.
-//   Bit#(1) addressMsb = ct.address[valueOf(VA_Width)-1];
-//   if (!ct.validAddress) addressMsb = ^addressMsb;
-//   return pack(CapabilityInMemory{
-//                 isCapability: True,
-//                 perms: ct.perms,
-//                 reserved: 0,
-//                 flags: ct.flags,
-//                 otype: otype_unsealed,
-//                 delta: ct.delta,
-//                 bounds: ct.bounds,
-//                 address: signExtend({addressMsb,ct.address})
-//   });
-// endfunction
+function CapTrim  trimCap(CapMem cm);
+  CapabilityInMemory cap = unpack(cm);
+  Bit#(TSub#(CapAddrW,VA_Width)) addr_upper = truncateLSB(cap.address);
+  return CapTrim{perms: cap.perms,
+                 flags: cap.flags,
+                 bounds: cap.bounds,  
+                 address: truncate(cap.address),
+                 validAddress: (addr_upper==signExtend(cap.address[valueOf(VA_Width)-1]))
+  };
+endfunction
+function CapMem untrimCap(CapTrim ct);
+  // Encode an invalid address as the bit above the last valid bit being different.
+  Bit#(1) addressMsb = ct.address[valueOf(VA_Width)-1];
+  if (!ct.validAddress) addressMsb = ^addressMsb;
+  return pack(CapabilityInMemory{
+                isCapability: True,
+                perms: ct.perms,
+                reserved: 0,
+                flags: ct.flags,
+                otype: otype_unsealed,
+                bounds: ct.bounds,
+                address: signExtend({addressMsb,ct.address})
+  });
+endfunction
 
 endpackage
diff --git a/CHERICap.bsv b/CHERICap.bsv
index 9a79968..b7a203a 100644
--- a/CHERICap.bsv
+++ b/CHERICap.bsv
@@ -119,7 +119,7 @@ endfunction
 
 // XXX TODO augment with all architectural bounds/ repbounds ?
 function Fmt showCHERICap (capT cap)
-  provisos (CHERICap #(capT , otypeW, flgW, addrW, inMemW, maskableW, delta));
+  provisos (CHERICap #(capT , otypeW, flgW, addrW, inMemW, maskableW));
   return $format( "Valid: 0x%0x", isValidCap(cap)) +
          $format(" Perms: 0x%0x", getPerms(cap)) +
          $format(" Kind: ", fshow(getKind(cap))) +
@@ -153,7 +153,6 @@ typeclass CHERICap #( type capT              // type of the CHERICap capability
                     , numeric type addrW     // width of the address
                     , numeric type inMemW    // width of the capability in mem
                     , numeric type maskableW // width of maskable bits
-                    , numeric type delta     // size of delta (tlb bypass)
                     )
   dependencies (capT determines (otypeW, flgW, addrW, inMemW, maskableW));