Add more comment on test suite

Author: ChinYikMing

tests/system/alignment/main.c

@@ -51,7 +51,13 @@ int main()
      * track) */
     TEST_LOGGER("MISALIGNED STORE TEST PASSED!\n");
 
-    /* misalign instuction fetch */
+    /*
+     * misalign instuction fetch
+     *
+     * MUST disable ENABLE_EXT_C when building rv32emu before running this test
+     * since jalr instruction only check misaligned if lacks of compressed
+     * instruction support
+     */
     misalign_func();
     /* execute the registered trap handler is considered a pass (use gdb to
      * track) */

tests/system/alignment/misalign.S

@@ -19,27 +19,27 @@ misalign_func:
 .section .text
 .global _start
 _start:
-    call main	
+    call main
     j exit
 
 # Assume three traps are delegated to supervisor,
 # so handle them using supervisor CSR
 .global misalign_trap_handler
 misalign_trap_handler:
     csrr t0, scause
-    
+
     # Check for misaligned instruction fetch
     li t1, CAUSE_MISALIGNED_INSN_FETCH
     beq t0, t1, misaligned_insn_fetch_handler
-    
+
     # Check for misaligned load
     li t1, CAUSE_MISALIGNED_LOAD
     beq t0, t1, misaligned_load_handler
-    
+
     # Check for misaligned store
     li t1, CAUSE_MISALIGNED_STORE
     beq t0, t1, misaligned_store_handler
-    
+
     # If none of the above, exit failed
 fail:
     li a0, 1
@@ -67,4 +67,3 @@ misaligned_store_handler:
     addi t0, t0, 4
     csrw sepc, t0
     sret
-