fix Issue 2617 - asm silently accepts ambiguous-sized operations

dlang · Aug 21, 2020 · 8b5785d · 8b5785d
1 parent 9cb3a52
commit 8b5785d
Showing 1 changed file with 28 additions and 3 deletions.
diff --git a/src/dmd/iasmdmd.d b/src/dmd/iasmdmd.d
@@ -773,14 +773,15 @@ RETRY:
 
         case 1:
         {
-            //printf("opflags1 = "); asm_output_flags(opflags1); printf("\n");
+            enum log = false;
+            if (log) { printf("opflags1 = "); asm_output_flags(opflags[0]); printf("\n"); }
             PTRNTAB1 *table1;
             for (table1 = pop.ptb.pptb1; table1.opcode != ASM_END;
                     table1++)
             {
-                //printf("table    = "); asm_output_flags(table1.usOp1); printf("\n");
+                if (log) { printf("table    = "); asm_output_flags(table1.usOp1); printf("\n"); }
                 const bMatch1 = asm_match_flags(opflags[0], table1.usOp1);
-                //printf("bMatch1 = x%x\n", bMatch1);
+                if (log) { printf("bMatch1 = x%x\n", bMatch1); }
                 if (bMatch1)
                 {
                     if (table1.opcode == 0x68 &&
@@ -796,6 +797,16 @@ RETRY:
                         continue;
                     }
 
+                    // Check for ambiguous size
+                    if (getOpndSize(opflags[0]) == OpndSize._anysize &&
+                        !opnds[0].bPtr &&
+                        (table1 + 1).opcode != ASM_END &&
+                        getOpndSize(table1.usOp1) == OpndSize._8)
+                    {
+                        asmerr("operand size for opcode `%s` is ambiguous, add `ptr byte/short/int/long` prefix", asm_opstr(pop));
+                        break RETRY;
+                    }
+
                     break;
                 }
                 if ((asmstate.ucItype == ITimmed) &&
@@ -896,8 +907,22 @@ RETRY:
                             }
                         }
                     }
+
+                    // Check for ambiguous size
+                    if (getOpndSize(opflags[0]) == OpndSize._anysize &&
+                        !opnds[0].bPtr &&
+                        opflags[1] == 0 &&
+                        table2.usOp2 == 0 &&
+                        (table2 + 1).opcode != ASM_END &&
+                        getOpndSize(table2.usOp1) == OpndSize._8)
+                    {
+                        asmerr("operand size for opcode `%s` is ambiguous, add `ptr byte/short/int/long` prefix", asm_opstr(pop));
+                        break RETRY;
+                    }
+
                     break;
                 }
+
                 if (asmstate.ucItype == ITopt ||
                     asmstate.ucItype == ITfloat)
                 {