Merge pull request #2473 from XavierAubert/cv32e40p/fix_another_compress_reg_issue

CV32E40Pv2 another case of conflict around compress reg fixed

Author: pascalgouedo

cv32e40p/env/corev-dv/cv32e40p_instr_base_test.sv

@@ -46,6 +46,7 @@ class cv32e40p_instr_base_test extends corev_instr_base_test;
     override_debug_rom_gen();
     override_instr_stream();
     override_load_store_lib();
+    override_loop_instr();
     super.build_phase(phase);
   endfunction
 
@@ -133,6 +134,11 @@ class cv32e40p_instr_base_test extends corev_instr_base_test;
     uvm_factory::get().set_type_override_by_type(riscv_mem_region_stress_test::get_type(), cv32e40p_mem_region_stress_test::get_type());
   endfunction
 
+  // to avoid loop tests to reserve all S0:A5 regs used by compressed instructions
+  virtual function void override_loop_instr();
+    uvm_factory::get().set_type_override_by_type(riscv_loop_instr::get_type(), cv32e40p_loop_instr::get_type());
+  endfunction
+
   virtual function void apply_directed_instr();
   endfunction
 

cv32e40p/env/corev-dv/cv32e40p_instr_test_pkg.sv

@@ -114,6 +114,7 @@ package cv32e40p_instr_test_pkg;
   `include "cv32e40p_debug_rom_gen.sv"
   `include "cv32e40p_asm_program_gen.sv"
   `include "cv32e40p_load_store_instr_lib.sv"
+  `include "cv32e40p_loop_instr.sv"
 
   `include "cv32e40p_instr_base_test.sv"
 

cv32e40p/env/corev-dv/cv32e40p_loop_instr.sv

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2018 Google LLC
+ * Copyright 2024 Dolphin Design
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+*/
+
+class cv32e40p_loop_instr extends riscv_loop_instr;
+    rand int          loop_cnt_has_taken_avail_comp_reg[];
+    rand int          loop_limit_has_taken_avail_comp_reg[];
+    riscv_reg_t       s0_a5_avail_regs[];
+
+    constraint with_compress_instructions_c {
+        loop_cnt_has_taken_avail_comp_reg.size() == loop_cnt_reg.size();
+        loop_limit_has_taken_avail_comp_reg.size() == loop_limit_reg.size();
+        foreach(loop_cnt_reg[i]) {
+            if (loop_cnt_reg[i] inside {s0_a5_avail_regs}) {
+                loop_cnt_has_taken_avail_comp_reg[i] == 1;
+            } else {
+                loop_cnt_has_taken_avail_comp_reg[i] == 0;
+            }
+        }
+        foreach(loop_limit_reg[i]) {
+            if (loop_limit_reg[i] inside {s0_a5_avail_regs}) {
+                loop_limit_has_taken_avail_comp_reg[i] == 1;
+            } else {
+                loop_limit_has_taken_avail_comp_reg[i] == 0;
+            }
+        }
+        // to make sure at least one is left for compress instructions
+        // count the number of ones (= taken comp regs), and contraint it to be less than the number of avail regs
+        if (cfg.disable_compressed_instr == 0) {
+          loop_cnt_has_taken_avail_comp_reg.sum() + loop_limit_has_taken_avail_comp_reg.sum() < s0_a5_avail_regs.size();
+        }
+    }
+
+    `uvm_object_utils(cv32e40p_loop_instr)
+    `uvm_object_new
+
+    function void pre_randomize();
+      super.pre_randomize();
+      s0_a5_avail_regs = {S0, S1, A0, A1, A2, A3, A4, A5};
+      s0_a5_avail_regs = s0_a5_avail_regs.find() with (!(item inside {cfg.reserved_regs, reserved_rd}));
+    endfunction
+
+endclass