Runtime routines to support tracing.
Currently includes code to hash pointers to sequence numbers.
The hash table should be separated out into a separate file
since that is generic. The rest of this code is pretty small.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2655 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/runtime/libtrace/Makefile b/runtime/libtrace/Makefile
new file mode 100644
index 0000000..18110e2
--- /dev/null
+++ b/runtime/libtrace/Makefile
@@ -0,0 +1,26 @@
+LEVEL = ../../..
+
+include $(LEVEL)/Makefile.common
+
+LIB32 = ../Output/libinstr32.a
+LIB64 = ../Output/libinstr64.a
+all:: $(LIB32) $(LIB64)
+
+tracelib: tracelib.c
+ g++ -g -DTEST_INSTRLIB $< -o $@
+
+Debug/tracelib32.o: tracelib.c Debug/.dir
+ g++ -c -g $< -o $@
+
+Debug/tracelib64.o: tracelib.c Debug/.dir
+ cc -c -xarch=v9 -g $< -o $@
+
+$(LIB32): Debug/tracelib32.o ../Output/.dir
+ ar r $@ $<
+
+$(LIB64): Debug/tracelib64.o ../Output/.dir
+ ar r $@ $<
+
+test: tracelib
+
+tracelib.c: tracelib.h
diff --git a/runtime/libtrace/tracelib.c b/runtime/libtrace/tracelib.c
new file mode 100644
index 0000000..35c9ccc
--- /dev/null
+++ b/runtime/libtrace/tracelib.c
@@ -0,0 +1,365 @@
+/*===-- Libraries/tracelib.c - Runtime routines for tracing -----*- C++ -*--===
+ *
+ * Runtime routines for supporting tracing of execution
+ * for code generated by LLVM.
+ *
+ *===---------------------------------------------------------------------===*/
+
+#include "tracelib.h"
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+
+/*===---------------------------------------------------------------------=====
+ * HASH FUNCTIONS
+ *===---------------------------------------------------------------------===*/
+
+/* use #defines until we have inlining */
+
+typedef int64_t Generic;
+typedef uint64_t Index;
+typedef ptrdiff_t Pointer;
+
+/* Index IntegerHashFunc(const Generic value, const Index size) */
+#define IntegerHashFunc(value, size) \
+ (value % size)
+
+/* Index IntegerRehashFunc(const Generic oldHashValue, const Index size) */
+#define IntegerRehashFunc(oldHashValue, size) \
+ ((oldHashValue+16) % size) /* 16 is relatively prime to a Mersenne prime! */
+
+/* Index PointerHashFunc(const void* value, const Index size) */
+#define PointerHashFunc(value, size) \
+ IntegerHashFunc((Pointer) value, size)
+
+/* Index PointerRehashFunc(const void* value, const Index size) */
+#define PointerRehashFunc(value, size) \
+ IntegerRehashFunc((Pointer) value, size)
+
+
+/*===---------------------------------------------------------------------=====
+ * POINTER-TO-GENERIC HASH TABLE.
+ * These should be moved to a separate location: HashTable.[ch]
+ *===---------------------------------------------------------------------===*/
+
+typedef enum { FIND, ENTER } ACTION;
+typedef char FULLEMPTY;
+const FULLEMPTY EMPTY = '\0';
+const FULLEMPTY FULL = '\1';
+
+const uint MAX_NUM_PROBES = 4;
+
+typedef struct PtrValueHashEntry_struct {
+ void* key;
+ Generic value;
+} PtrValueHashEntry;
+
+typedef struct PtrValueHashTable_struct {
+ PtrValueHashEntry* table;
+ FULLEMPTY* fullEmptyFlags;
+ Index capacity;
+ Index size;
+} PtrValueHashTable;
+
+
+extern Generic LookupOrInsertPtr(PtrValueHashTable* ptrTable,
+ void* ptr, ACTION action);
+
+extern void Insert(PtrValueHashTable* ptrTable, void* ptr, Generic value);
+
+extern void Delete(PtrValueHashTable* ptrTable, void* ptr);
+
+
+void
+InitializeTable(PtrValueHashTable* ptrTable, Index newSize)
+{
+ ptrTable->table = (PtrValueHashEntry*) malloc(newSize *
+ sizeof(PtrValueHashEntry));
+ ptrTable->fullEmptyFlags = (FULLEMPTY*) malloc(newSize * sizeof(FULLEMPTY));
+ memset(ptrTable->fullEmptyFlags, '\0', newSize * sizeof(FULLEMPTY));
+ ptrTable->capacity = newSize;
+ ptrTable->size = 0;
+}
+
+PtrValueHashTable*
+CreateTable(Index initialSize)
+{
+ PtrValueHashTable* ptrTable =
+ (PtrValueHashTable*) malloc(sizeof(PtrValueHashTable));
+ InitializeTable(ptrTable, initialSize);
+ return ptrTable;
+}
+
+void
+ReallocTable(PtrValueHashTable* ptrTable, Index newSize)
+{
+ if (newSize > ptrTable->capacity)
+ {
+ unsigned int i;
+
+ PtrValueHashEntry* oldTable = ptrTable->table;
+ FULLEMPTY* oldFlags = ptrTable->fullEmptyFlags;
+ Index oldSize = ptrTable->size;
+
+ /* allocate the new storage and flags and re-insert the old entries */
+ InitializeTable(ptrTable, newSize);
+ for (i=0; i < oldSize; ++i)
+ Insert(ptrTable, oldTable[i].key, oldTable[i].value);
+ assert(ptrTable->size == oldSize);
+
+ free(oldTable);
+ free(oldFlags);
+ }
+}
+
+void
+DeleteTable(PtrValueHashTable* ptrTable)
+{
+ free(ptrTable->table);
+ free(ptrTable->fullEmptyFlags);
+ memset(ptrTable, '\0', sizeof(PtrValueHashTable));
+ free(ptrTable);
+}
+
+void
+InsertAtIndex(PtrValueHashTable* ptrTable, void* ptr, Generic value, Index index)
+{
+ assert(ptrTable->fullEmptyFlags[index] == EMPTY && "Slot is in use!");
+ ptrTable->table[index].key = ptr;
+ ptrTable->table[index].value = value;
+ ptrTable->fullEmptyFlags[index] = FULL;
+ ptrTable->size++;
+}
+
+void
+DeleteAtIndex(PtrValueHashTable* ptrTable, Index index)
+{
+ assert(ptrTable->fullEmptyFlags[index] == FULL && "Deleting empty slot!");
+ ptrTable->table[index].key = NULL;
+ ptrTable->table[index].value = (Generic) NULL;
+ ptrTable->fullEmptyFlags[index] = EMPTY;
+ ptrTable->size--;
+}
+
+Index
+FindIndex(PtrValueHashTable* ptrTable, void* ptr)
+{
+ uint numProbes = 1;
+ Index index = PointerHashFunc(ptr, ptrTable->capacity);
+ if (ptrTable->fullEmptyFlags[index] == FULL)
+ {
+ if (ptrTable->table[index].key == ptr)
+ return index;
+
+ /* First lookup failed on non-empty slot: probe further */
+ while (numProbes < MAX_NUM_PROBES)
+ {
+ index = PointerRehashFunc(index, ptrTable->capacity);
+ if (ptrTable->fullEmptyFlags[index] == EMPTY)
+ break;
+ else if (ptrTable->table[index].key == ptr)
+ return index;
+ ++numProbes;
+ }
+ }
+
+ /* Lookup failed: item is not in the table. */
+ /* If last slot is empty, use that slot. */
+ /* Otherwise, table must have been reallocated, so search again. */
+
+ if (numProbes == MAX_NUM_PROBES)
+ { /* table is too full: reallocate and search again */
+ ReallocTable(ptrTable, 1 + 2*ptrTable->capacity);
+ return FindIndex(ptrTable, ptr);
+ }
+ else
+ {
+ assert(ptrTable->fullEmptyFlags[index] == EMPTY &&
+ "Stopped before finding an empty slot and before MAX probes!");
+ return index;
+ }
+}
+
+Generic
+LookupOrInsertPtr(PtrValueHashTable* ptrTable, void* ptr, ACTION action)
+{
+ Index index = FindIndex(ptrTable, ptr);
+ if (ptrTable->fullEmptyFlags[index] == FULL &&
+ ptrTable->table[index].key == ptr)
+ return ptrTable->table[index].value;
+
+ /* Lookup failed: item is not in the table */
+ if (action != ENTER)
+ return (Generic) NULL;
+
+ /* Insert item into the table and return its index */
+ InsertAtIndex(ptrTable, ptr, (Generic) NULL, index);
+ return (Generic) NULL;
+}
+
+/* Returns NULL if the item is not found. */
+/* void* LookupPtr(PtrValueHashTable* ptrTable, void* ptr) */
+#define LookupPtr(ptrTable, ptr) \
+ LookupOrInsertPtr(ptrTable, ptr, FIND)
+
+void
+Insert(PtrValueHashTable* ptrTable, void* ptr, Generic value)
+{
+ Index index = FindIndex(ptrTable, ptr);
+ assert(ptrTable->fullEmptyFlags[index] == EMPTY &&
+ "ptr is already in the table: delete it first!");
+ InsertAtIndex(ptrTable, ptr, value, index);
+}
+
+void
+Delete(PtrValueHashTable* ptrTable, void* ptr)
+{
+ Index index = FindIndex(ptrTable, ptr);
+ if (ptrTable->fullEmptyFlags[index] == FULL &&
+ ptrTable->table[index].key == ptr)
+ {
+ DeleteAtIndex(ptrTable, index);
+ }
+}
+
+/*===---------------------------------------------------------------------=====
+ * RUNTIME ROUTINES TO MAP POINTERS TO SEQUENCE NUMBERS
+ *===---------------------------------------------------------------------===*/
+
+PtrValueHashTable* SequenceNumberTable = NULL;
+Index INITIAL_SIZE = 1 << 18;
+
+#define MAX_NUM_SAVED 1024
+
+typedef struct PointerSet_struct {
+ char* savedPointers[MAX_NUM_SAVED]; /* 1024 alloca'd ptrs shd suffice */
+ unsigned int numSaved;
+ struct PointerSet_struct* nextOnStack; /* implement a cheap stack */
+} PointerSet;
+
+PointerSet* topOfStack = NULL;
+
+SequenceNumber
+HashPointerToSeqNum(char* ptr)
+{
+ static SequenceNumber count = 0;
+ SequenceNumber seqnum;
+ if (SequenceNumberTable == NULL) {
+ assert(MAX_NUM_PROBES < INITIAL_SIZE+1 && "Initial size too small");
+ SequenceNumberTable = CreateTable(INITIAL_SIZE);
+ }
+ seqnum = (SequenceNumber) LookupPtr(SequenceNumberTable, ptr);
+ if (seqnum == 0)
+ {
+ Insert(SequenceNumberTable, ptr, ++count);
+ seqnum = count;
+ }
+ return seqnum;
+}
+
+void
+ReleasePointerSeqNum(char* ptr)
+{ /* if a sequence number was assigned to this ptr, release it */
+ SequenceNumber seqnum;
+ if (SequenceNumberTable != NULL)
+ Delete(SequenceNumberTable, ptr);
+}
+
+void
+PushPointerSet()
+{
+ PointerSet* newSet = (PointerSet*) malloc(sizeof(PointerSet));
+ newSet->numSaved = 0;
+ newSet->nextOnStack = topOfStack;
+ topOfStack = newSet;
+}
+
+void
+PopPointerSet()
+{
+ PointerSet* oldSet;
+ assert(topOfStack != NULL && "popping from empty stack!");
+ oldSet = topOfStack;
+ topOfStack = oldSet->nextOnStack;
+ assert(oldSet->numSaved == 0);
+ free(oldSet);
+}
+
+/* free the pointers! */
+static void
+ReleaseRecordedPointers(char* savedPointers[MAX_NUM_SAVED],
+ unsigned int numSaved)
+{
+ unsigned int i;
+ for (i=0; i < topOfStack->numSaved; ++i)
+ ReleasePointerSeqNum(topOfStack->savedPointers[i]);
+}
+
+void
+ReleasePointersPopSet()
+{
+ ReleaseRecordedPointers(topOfStack->savedPointers, topOfStack->numSaved);
+ topOfStack->numSaved = 0;
+ PopPointerSet();
+}
+
+void
+RecordPointer(char* ptr)
+{ /* record pointers for release later */
+ if (topOfStack->numSaved == MAX_NUM_SAVED) {
+ printf("***\n*** WARNING: OUT OF ROOM FOR SAVED POINTERS."
+ " ALL POINTERS ARE BEING FREED.\n"
+ "*** THE SEQUENCE NUMBERS OF SAVED POINTERS WILL CHANGE!\n*** \n");
+ ReleaseRecordedPointers(topOfStack->savedPointers, topOfStack->numSaved);
+ topOfStack->numSaved = 0;
+ }
+ topOfStack->savedPointers[topOfStack->numSaved++] = ptr;
+}
+
+/*===---------------------------------------------------------------------=====
+ * TEST DRIVER FOR INSTRUMENTATION LIBRARY
+ *===---------------------------------------------------------------------===*/
+
+#ifndef TEST_INSTRLIB
+#undef TEST_INSTRLIB /* #define this to turn on by default */
+#endif
+
+#ifdef TEST_INSTRLIB
+int
+main(int argc, char** argv)
+{
+ int i, j;
+ int doRelease = 0;
+
+ INITIAL_SIZE = 5; /* start with small table to test realloc's*/
+
+ if (argc > 1 && ! strcmp(argv[1], "-r"))
+ {
+ PushPointerSet();
+ doRelease = 1;
+ }
+
+ for (i=0; i < argc; ++i)
+ for (j=0; argv[i][j]; ++j)
+ {
+ printf("Sequence number for argc[%d][%d] (%c) = Hash(%p) = %d\n",
+ i, j, argv[i][j], argv[i]+j, HashPointerToSeqNum(argv[i]+j));
+
+ if (doRelease)
+ RecordPointer(argv[i]+j);
+ }
+
+ if (doRelease)
+ ReleasePointersPopSet();
+
+ /* print sequence numbers out again to compare with (-r) and w/o release */
+ for (i=argc-1; i >= 0; --i)
+ for (j=0; argv[i][j]; ++j)
+ printf("Sequence number for argc[%d][%d] (%c) = Hash(%p) = %d\n",
+ i, j, argv[i][j], argv[i]+j, HashPointerToSeqNum(argv[i]+j));
+
+ return 0;
+}
+#endif
diff --git a/runtime/libtrace/tracelib.h b/runtime/libtrace/tracelib.h
new file mode 100644
index 0000000..493e703
--- /dev/null
+++ b/runtime/libtrace/tracelib.h
@@ -0,0 +1,40 @@
+/*===-- Libraries/tracelib.h - Runtime routines for tracing -----*- C++ -*--===
+ *
+ * Runtime routines for supporting tracing of execution
+ * for code generated by LLVM.
+ *
+ *===---------------------------------------------------------------------===*/
+
+#ifndef _TEST_LIBRARIES_LIBINSTR_TRACELIB_
+#define _TEST_LIBRARIES_LIBINSTR_TRACELIB_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <sys/types.h>
+
+/*===---------------------------------------------------------------------=====
+ * Support for tracing pointers
+ *===---------------------------------------------------------------------===*/
+
+typedef unsigned int SequenceNumber;
+
+extern SequenceNumber HashPointerToSeqNum( char* ptr);
+
+extern void ReleasePointerSeqNum(char* ptr);
+
+extern void RecordPointer(char* ptr);
+
+extern void PushPointerSet();
+
+extern void ReleasePointersPopSet();
+
+
+#ifdef __cplusplus
+}
+#endif
+
+/*===---------------------------------------------------------------------===*/
+
+#endif _TEST_LIBRARIES_LIBINSTR_TRACELIB_