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New functions CS_ResetMarks, CS_ResetAllMarks and CS_IsBasicBlock.

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git-svn-id: svn://svn.cc65.org/cc65/trunk@1448 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2002-10-06 19:01:16 +00:00
parent 62b3576f5f
commit 1647c6783f
2 changed files with 153 additions and 10 deletions
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120
src/cc65/codeseg.c
View File

@ -1096,6 +1096,126 @@ void CS_DelCodeAfter (CodeSeg* S, unsigned Last)
void CS_ResetMarks (CodeSeg* S, unsigned First, unsigned Last)
/* Remove all user marks from the entries in the given range */
{
while (First <= Last) {
CE_ResetMark (CS_GetEntry (S, First++));
}
}
int CS_IsBasicBlock (CodeSeg* S, unsigned First, unsigned Last)
/* Check if the given code segment range is a basic block. That is, check if
* First is the only entrance and Last is the only exit. This means that no
* jump/branch inside the block may jump to an insn below First or after(!)
* Last, and that no insn may jump into this block from the outside.
*/
{
unsigned I;
/* Don't accept invalid ranges */
CHECK (First <= Last);
/* First pass: Walk over the range and remove all marks from the entries */
CS_ResetMarks (S, First, Last);
/* Second pass: Walk over the range checking all labels. Note: There may be
* label on the first insn which is ok.
*/
I = First + 1;
while (I <= Last) {
/* Get the next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check if this entry has one or more labels, if so, check which
* entries jump to this label.
*/
unsigned LabelCount = CE_GetLabelCount (E);
unsigned LabelIndex;
for (LabelIndex = 0; LabelIndex < LabelCount; ++LabelIndex) {
/* Get this label */
CodeLabel* L = CE_GetLabel (E, LabelIndex);
/* Walk over all entries that jump to this label. Check for each
* of the entries if it is out of the range.
*/
unsigned RefCount = CL_GetRefCount (L);
unsigned RefIndex;
for (RefIndex = 0; RefIndex < RefCount; ++RefIndex) {
/* Get the code entry that jumps here */
CodeEntry* Ref = CL_GetRef (L, RefIndex);
/* Walk over out complete range and check if we find the
* refering entry. This is cheaper than using CS_GetEntryIndex,
* because CS_GetEntryIndex will search the complete code
* segment and not just our range.
*/
unsigned J;
for (J = First; J <= Last; ++J) {
if (Ref == CS_GetEntry (S, J)) {
break;
}
}
if (J > Last) {
/* We did not find the entry. This means that the jump to
* out code segment entry E came from outside the range,
* which in turn means that the given range is not a basic
* block.
*/
CS_ResetMarks (S, First, Last);
return 0;
}
/* If we come here, we found the entry. Mark it, so we know
* that the branch to the label is in range.
*/
CE_SetMark (Ref);
}
}
/* Next entry */
++I;
}
/* Third pass: Walk again over the range and check all branches. If we
* find a branch that is not marked, its target is not inside the range
* (since we checked all the labels in the range before).
*/
I = First;
while (I <= Last) {
/* Get the next entry */
CodeEntry* E = CS_GetEntry (S, I);
/* Check if this is a branch and if so, if it has a mark */
if (E->Info & (OF_UBRA | OF_CBRA)) {
if (!CE_HasMark (E)) {
/* No mark means not a basic block. Before bailing out, be sure
* to remove the marks from the remaining entries.
*/
CS_ResetMarks (S, I+1, Last);
return 0;
}
/* Remove the mark */
CE_ResetMark (E);
}
/* Next entry */
++I;
}
/* Done - this is a basic block */
return 1;
}
void CS_OutputPrologue (const CodeSeg* S, FILE* F)
/* If the given code segment is a code segment for a function, output the
* assembler prologue into the file. That is: Output a comment header, switch

43
src/cc65/codeseg.h
View File

@ -103,6 +103,16 @@ void CS_AddVLine (CodeSeg* S, LineInfo* LI, const char* Format, va_list ap) attr
void CS_AddLine (CodeSeg* S, LineInfo* LI, const char* Format, ...) attribute ((format(printf,3,4)));
/* Add a line to the given code segment */
#if defined(HAVE_INLINE)
INLINE unsigned CS_GetEntryCount (const CodeSeg* S)
/* Return the number of entries for the given code segment */
{
return CollCount (&S->Entries);
}
#else
# define CS_GetEntryCount(S) CollCount (&(S)->Entries)
#endif
void CS_InsertEntry (CodeSeg* S, struct CodeEntry* E, unsigned Index);
/* Insert the code entry at the index given. Following code entries will be
* moved to slots with higher indices.
@ -218,6 +228,29 @@ void CS_MoveLabelRef (CodeSeg* S, struct CodeEntry* E, CodeLabel* L);
void CS_DelCodeAfter (CodeSeg* S, unsigned Last);
/* Delete all entries including the given one */
void CS_ResetMarks (CodeSeg* S, unsigned First, unsigned Last);
/* Remove all user marks from the entries in the given range */
#if defined(HAVE_INLINE)
INLINE void CS_ResetAllMarks (CodeSeg* S)
/* Remove all user marks from the code segment */
{
if (CS_GetEntryCount (S) > 0) {
CS_ResetMarks (S, 0, CS_GetEntryCount (S));
}
}
#else
# define CS_ResetAllMarks(S) \
((CS_GetEntryCount (S) > 0)? CS_ResetMarks (S, 0, CS_GetEntryCount (S)) : (void) 0)
#endif
int CS_IsBasicBlock (CodeSeg* S, unsigned First, unsigned Last);
/* Check if the given code segment range is a basic block. That is, check if
* First is the only entrance and Last is the only exit. This means that no
* jump/branch inside the block may jump to an insn below First or after(!)
* Last, and that no insn may jump into this block from the outside.
*/
void CS_OutputPrologue (const CodeSeg* S, FILE* F);
/* If the given code segment is a code segment for a function, output the
* assembler prologue into the file. That is: Output a comment header, switch
@ -233,16 +266,6 @@ void CS_OutputEpilogue (const CodeSeg* S, FILE* F);
void CS_Output (const CodeSeg* S, FILE* F);
/* Output the code segment data to a file */
#if defined(HAVE_INLINE)
INLINE unsigned CS_GetEntryCount (const CodeSeg* S)
/* Return the number of entries for the given code segment */
{
return CollCount (&S->Entries);
}
#else
# define CS_GetEntryCount(S) CollCount (&(S)->Entries)
#endif
void CS_FreeRegInfo (CodeSeg* S);
/* Free register infos for all instructions */