From f71a3d61a9fa724f881829cd418f74fb966bee98 Mon Sep 17 00:00:00 2001
From: Yuecheng-CAM <yw737@cam.ac.uk>
Date: Sun, 20 Oct 2024 23:17:01 +0100
Subject: [PATCH] implement C_GET_HIGH

---
 src_Core/ISA/ISA_Decls_CHERI.bsv           | 4 +++-
 src_Core/RISCY_OOO/procs/lib/Decode.bsv    | 7 +++++++
 src_Core/RISCY_OOO/procs/lib/Exec.bsv      | 2 ++
 src_Core/RISCY_OOO/procs/lib/ProcTypes.bsv | 1 +
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src_Core/ISA/ISA_Decls_CHERI.bsv b/src_Core/ISA/ISA_Decls_CHERI.bsv
index 3dbd9dd..4e02d05 100755
--- a/src_Core/ISA/ISA_Decls_CHERI.bsv
+++ b/src_Core/ISA/ISA_Decls_CHERI.bsv
@@ -186,7 +186,9 @@ Bit #(5) f5rs2_cap_CSealEntry  = 5'h11;
 Bit #(5) f5rs2_cap_CLoadTags   = 5'h12;
 // 5'h13 unused
 Bit #(5) f5rs2_cap_JALR_PCC    = 5'h14;
-// 5'h15-5'h1f unused (5'h1f reserved for 1-reg instructions)
+// 5'h15-5'h16 unused
+Bit #(5) f5rs2_cap_CGetHigh    = 5'h17;
+// 5'h18-5'h1f unused (5'h1f reserved for 1-reg instructions)
 
 // ================================================================
 // f7_cap_{Load, Store} opcode subdivision
diff --git a/src_Core/RISCY_OOO/procs/lib/Decode.bsv b/src_Core/RISCY_OOO/procs/lib/Decode.bsv
index c79ea97..a0cd47e 100644
--- a/src_Core/RISCY_OOO/procs/lib/Decode.bsv
+++ b/src_Core/RISCY_OOO/procs/lib/Decode.bsv
@@ -1327,6 +1327,13 @@ function DecodeResult decode(Instruction inst, Bool cap_mode);
                                     regs.src1 = Valid(tagged Gpr rs1);
                                     dInst.capFunc = CapInspect (GetType);
                                 end
+                                f5rs2_cap_CGetHigh: begin
+                                    legalInst = True;
+                                    dInst.iType = Cap;
+                                    regs.dst = Valid(tagged Gpr rd);
+                                    regs.src1 = Valid(tagged Gpr rs1);
+                                    dInst.capFunc = CapInspect (GetHigh);
+                                end
                                 f5rs2_cap_CLoadTags: begin
                                     legalInst = True;
                                     dInst.iType = Ld;
diff --git a/src_Core/RISCY_OOO/procs/lib/Exec.bsv b/src_Core/RISCY_OOO/procs/lib/Exec.bsv
index c408936..a322162 100644
--- a/src_Core/RISCY_OOO/procs/lib/Exec.bsv
+++ b/src_Core/RISCY_OOO/procs/lib/Exec.bsv
@@ -308,6 +308,8 @@ function Data capInspect(CapPipe a, CapPipe b, CapInspectFunc func);
                    zeroExtend(getFlags(a));
                tagged GetPerm                :
                    zeroExtend(getPerms(a));
+               tagged GetHigh                :
+                   zeroExtend(tpl_2(toMem(a))[127:64]);
                tagged GetType                :
                    tpl_1(extractType(a));
                tagged ToPtr                  :
diff --git a/src_Core/RISCY_OOO/procs/lib/ProcTypes.bsv b/src_Core/RISCY_OOO/procs/lib/ProcTypes.bsv
index 208a2e6..fdb4da5 100644
--- a/src_Core/RISCY_OOO/procs/lib/ProcTypes.bsv
+++ b/src_Core/RISCY_OOO/procs/lib/ProcTypes.bsv
@@ -363,6 +363,7 @@ typedef union tagged {
     void GetFlags;
     void GetPerm;
     void GetType;
+    void GetHigh;
     void ToPtr;
 } CapInspectFunc deriving(Bits, Eq, FShow);