Added a new CS_RangeHasLabel function

git-svn-id: svn://svn.cc65.org/cc65/trunk@1058 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/src/cc65/codeseg.c b/src/cc65/codeseg.c
index bbc21337a4170e0328a1d9317c96e9db108ffb43..99497da07bb5a59342a6f8f379e5f61e8e312381 100644 (file)
--- a/src/cc65/codeseg.c
+++ b/src/cc65/codeseg.c
@@ -161,7 +161,7 @@ static void CS_RemoveLabelFromHash (CodeSeg* S, CodeLabel* L)
 
 
 static CodeLabel* CS_AddLabelInternal (CodeSeg* S, const char* Name,
-                                      void (*ErrorFunc) (const char*, ...))
+                                      void (*ErrorFunc) (const char*, ...))
 /* Add a code label for the next instruction to follow */
 {
     /* Calculate the hash from the name */
@@ -725,6 +725,36 @@ unsigned CS_GetEntryIndex (CodeSeg* S, struct CodeEntry* E)
 
 
 
+int CS_RangeHasLabel (CodeSeg* S, unsigned Start, unsigned Count)
+/* Return true if any of the code entries in the given range has a label
+ * attached. If the code segment does not span the given range, check the
+ * possible span instead.
+ */
+{
+    unsigned EntryCount = CS_GetEntryCount(S);
+
+    /* Adjust count. We expect at least Start to be valid. */
+    CHECK (Start < EntryCount);
+    if (Start + Count > EntryCount) {
+       Count = EntryCount - Start;
+    }
+
+    /* Check each entry. Since we have validated the index above, we may
+     * use the unchecked access function in the loop which is faster.
+     */
+    while (Count--) {
+       const CodeEntry* E = CollAtUnchecked (&S->Entries, Start++);
+       if (CE_HasLabel (E)) {
+           return 1;
+       }
+    }
+    
+    /* No label in the complete range */
+    return 0;
+}
+
+
+
 CodeLabel* CS_AddLabel (CodeSeg* S, const char* Name)
 /* Add a code label for the next instruction to follow */
 {
@@ -806,6 +836,7 @@ void CS_MergeLabels (CodeSeg* S)
  */
 {
     unsigned I;
+    unsigned J;
 
     /* First, remove all labels from the label symbol table that don't have an
      * owner (this means that they are actually external labels but we didn't
@@ -817,12 +848,25 @@ void CS_MergeLabels (CodeSeg* S)
        CodeLabel** L = &S->LabelHash[I];
        while (*L) {
            if ((*L)->Owner == 0) {
-               /* The label does not have an owner, remove it from the chain */
+
+               /* The label does not have an owner, remove it from the chain */
                CodeLabel* X = *L;
                        *L = X->Next;
+
+               /* Cleanup any entries jumping to this label */
+               for (J = 0; J < CL_GetRefCount (X); ++J) {
+                   /* Get the entry referencing this label */
+                   CodeEntry* E = CL_GetRef (X, J);
+                   /* And remove the reference */
+                   E->JumpTo = 0;
+               }
+
+               /* Print some debugging output */
                if (Debug) {
                    printf ("Removing unused global label `%s'", X->Name);
                }
+
+               /* And free the label */
                FreeCodeLabel (X);
            } else {
                /* Label is owned, point to next code label pointer */
@@ -1119,7 +1163,7 @@ void CS_GenRegInfo (CodeSeg* S)
 
        /* Assume we're done after this run */
        Done = 1;
-    
+
        /* On entry, the register contents are unknown */
        RC_Invalidate (&Regs);
        CurrentRegs = &Regs;
@@ -1194,33 +1238,33 @@ void CS_GenRegInfo (CodeSeg* S)
                    }
                    ++Entry;
                }
-    
+
                /* Use this register info */
                CurrentRegs = &Regs;
-    
+
            }
-    
+
            /* Generate register info for this instruction */
            CE_GenRegInfo (E, CurrentRegs);
-    
+
            /* Remember for the next insn if this insn was an uncondition branch */
            WasJump = (E->Info & OF_UBRA) != 0;
 
            /* Output registers for this insn are input for the next */
            CurrentRegs = &E->RI->Out;
-    
+
            /* If this insn is a branch on zero flag, we may have more info on
             * register contents for one of both flow directions, but only if
             * there is a previous instruction.
             */
            if ((E->Info & OF_ZBRA) != 0 && (P = CS_GetPrevEntry (S, I)) != 0) {
-    
+
                /* Get the branch condition */
                bc_t BC = GetBranchCond (E->OPC);
-    
+
                /* Check the previous instruction */
                switch (P->OPC) {
-    
+
                    case OP65_ADC:
                    case OP65_AND:
                    case OP65_DEA:
@@ -1237,7 +1281,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            E->RI->Out.RegA = 0;
                        }
                        break;
-    
+
                    case OP65_CMP:
                        /* If this is an immidiate compare, the A register has
                         * the value of the compare later.
@@ -1250,7 +1294,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            }
                        }
                        break;
-    
+
                    case OP65_CPX:
                        /* If this is an immidiate compare, the X register has
                         * the value of the compare later.
@@ -1263,7 +1307,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            }
                        }
                        break;
-    
+
                    case OP65_CPY:
                        /* If this is an immidiate compare, the Y register has
                         * the value of the compare later.
@@ -1276,7 +1320,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            }
                        }
                        break;
-    
+
                    case OP65_DEX:
                    case OP65_INX:
                    case OP65_LDX:
@@ -1288,7 +1332,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            E->RI->Out.RegX = 0;
                        }
                        break;
-    
+
                    case OP65_DEY:
                    case OP65_INY:
                    case OP65_LDY:
@@ -1300,7 +1344,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            E->RI->Out.RegY = 0;
                        }
                        break;
-    
+
                    case OP65_TAX:
                    case OP65_TXA:
                        /* If the branch is a beq, both A and X are zero at the
@@ -1313,7 +1357,7 @@ void CS_GenRegInfo (CodeSeg* S)
                            E->RI->Out.RegA = E->RI->Out.RegX = 0;
                        }
                        break;
-    
+
                    case OP65_TAY:
                    case OP65_TYA:
                        /* If the branch is a beq, both A and Y are zero at the
@@ -1326,10 +1370,10 @@ void CS_GenRegInfo (CodeSeg* S)
                            E->RI->Out.RegA = E->RI->Out.RegY = 0;
                        }
                        break;
-    
+
                    default:
                        break;
-    
+
                }
            }
        }

diff --git a/src/cc65/codeseg.h b/src/cc65/codeseg.h
index 40ceb77a189a549b89b3f056dac4b3686644187c..fc61ab25eb476790ef4d25cad27cf587c9b4e004 100644 (file)
--- a/src/cc65/codeseg.h
+++ b/src/cc65/codeseg.h
@@ -171,6 +171,12 @@ int CS_GetEntries (CodeSeg* S, struct CodeEntry** List,
 unsigned CS_GetEntryIndex (CodeSeg* S, struct CodeEntry* E);
 /* Return the index of a code entry */
 
+int CS_RangeHasLabel (CodeSeg* S, unsigned Start, unsigned Count);
+/* Return true if any of the code entries in the given range has a label
+ * attached. If the code segment does not span the given range, check the
+ * possible span instead.
+ */
+
 CodeLabel* CS_AddLabel (CodeSeg* S, const char* Name);
 /* Add a code label for the next instruction to follow */