add reprod examples for issues

reprod/6_precalc_fixed.core_desc

@@ -0,0 +1,24 @@
+// The compiler does not seem to precalculate fixed expressions
+// This can be seen e.g. as it breaks loop unrolling (see also dynamic_loop)
+
+InstructionSet Zbb {
+    architectural_state {
+        unsigned int XLEN=32;
+        const register unsigned<32> XLEN_R = 32;
+        register unsigned<XLEN> X[32] [[is_main_reg]];
+    }
+    instructions {
+        TEST {
+            encoding: 12'b011000000000 :: rs1[4:0] :: 3'b001 :: rd[4:0] :: 7'b0010011;
+            assembly: "{name(rd)}, {name(rs1)}";
+            behavior: {
+                        unsigned int count = XLEN_R;
+                        for(int i=0; i<=32-1; i++){
+                        //for(int i=0; i<=31; i++){
+                            count = 1;
+                        }
+                        X[rd] = count;
+                    }
+        }
+    }
+}