Xqccmp extension: Add stack exceptions and stack exceptions checks to IDL code of push/pop instructions

Signed-off-by: Albert Yosher <[email protected]>

Author: ayosher

cfgs/qc_iu/arch_overlay/ext/Xqccmp.yaml

@@ -43,9 +43,18 @@ versions:
     email: [email protected]
   changes:
     - Fix qc.cm.pushfp instruction to avoid rlist == 4, since not saving s0 == fp but updating it, should not occur
+    - Add list of supported custom exceptions - stack alignment check and stack range check
+    - Add stack exception checks in all push/pop instructions
   requires:
     name: Zca
     version: ">= 1.0.0"
+exception_codes:
+  - num: 27
+    name: Illegal Stack Pointer
+    var: IllegalStackPointer
+  - num: 28
+    name: Stack Pointer Out-Of-Range
+    var: SpOutOfRange
 description: |
   The Xqccmp extension is a set of instructions which may be executed as a series of existing 32-bit RISC-V instructions.
 

cfgs/qc_iu/arch_overlay/inst/Xqccmp/qc.cm.pop.yaml

@@ -40,6 +40,15 @@ operation(): |
   if (implemented?(ExtensionName::Xqccmp) && (CSR[misa].C == 1'b0)) {
     raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
   }
+  if (X[2] < CSR[qc.mstkbottomaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] > CSR[qc.mstktopaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] & 0xf != 0) {
+    raise(ExceptionCode::IllegalStackPointer, mode(), $encoding);
+  }
 
   XReg size = xlen();
   XReg nreg = (rlist == 15) ? 13 : (rlist - 3);

cfgs/qc_iu/arch_overlay/inst/Xqccmp/qc.cm.popret.yaml

@@ -40,6 +40,15 @@ operation(): |
   if (implemented?(ExtensionName::Xqccmp) && (CSR[misa].C == 1'b0)) {
     raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
   }
+  if (X[2] < CSR[qc.mstkbottomaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] > CSR[qc.mstktopaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] & 0xf != 0) {
+    raise(ExceptionCode::IllegalStackPointer, mode(), $encoding);
+  }
 
   XReg size = xlen();
   XReg nreg = (rlist == 15) ? 13 : (rlist - 3);

cfgs/qc_iu/arch_overlay/inst/Xqccmp/qc.cm.popretz.yaml

@@ -40,6 +40,15 @@ operation(): |
   if (implemented?(ExtensionName::Xqccmp) && (CSR[misa].C == 1'b0)) {
     raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
   }
+  if (X[2] < CSR[qc.mstkbottomaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] > CSR[qc.mstktopaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] & 0xf != 0) {
+    raise(ExceptionCode::IllegalStackPointer, mode(), $encoding);
+  }
 
   XReg size = xlen();
   XReg nreg = (rlist == 15) ? 13 : (rlist - 3);
@@ -48,7 +57,6 @@ operation(): |
   XReg virtual_address_new_sp = virtual_address_sp + stack_aligned_adj + spimm;
   XReg virtual_address_base = virtual_address_new_sp - size;
 
-
   X[ 1] = read_memory_xlen(virtual_address_base -  0*size, $encoding);
   if (nreg > 1) {
     X[ 8] = read_memory_xlen(virtual_address_base -  1*size, $encoding);

cfgs/qc_iu/arch_overlay/inst/Xqccmp/qc.cm.push.yaml

@@ -42,6 +42,15 @@ operation(): |
   if (implemented?(ExtensionName::Xqccmp) && (CSR[misa].C == 1'b0)) {
     raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
   }
+  if (X[2] < CSR[qc.mstkbottomaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] > CSR[qc.mstktopaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] & 0xf != 0) {
+    raise(ExceptionCode::IllegalStackPointer, mode(), $encoding);
+  }
 
   XReg size = xlen();
   XReg nreg = (rlist == 15) ? 13 : (rlist - 3);

cfgs/qc_iu/arch_overlay/inst/Xqccmp/qc.cm.pushfp.yaml

@@ -42,6 +42,15 @@ operation(): |
   if (implemented?(ExtensionName::Xqccmp) && (CSR[misa].C == 1'b0)) {
     raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
   }
+  if (X[2] < CSR[qc.mstkbottomaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] > CSR[qc.mstktopaddr]) {
+    raise(ExceptionCode::SpOutOfRange, mode(), $encoding);
+  }
+  if (X[2] & 0xf != 0) {
+    raise(ExceptionCode::IllegalStackPointer, mode(), $encoding);
+  }
 
   XReg size = xlen();
   XReg nreg = (rlist == 15) ? 13 : (rlist - 3);