Lots of changes from David Mosberger-Tang; see ChangeLog and NOTES for details:

Alpha support.
Long options.
New file format to support more information; backwards compatibility.
Line-level profiling, on systems where bfd_find_nearest_line works.
Selective display of data.

gprof/gmon_out.h

@@ -0,0 +1,46 @@
+/*
+ * This file specifies the format of gmon.out files.  It should have
+ * as few external dependencies as possible as it is going to be
+ * included in many different programs.  That is, minimize the
+ * number of #include's.
+ *
+ * A gmon.out file consists of a header (defined by gmon_hdr) followed
+ * by a sequence of records.  Each record starts with a one-byte tag
+ * identifying the type of records, followed by records specific data.
+ */
+#ifndef gmon_out_h
+#define gmon_out_h
+
+#define	GMON_MAGIC	"gmon"	/* magic cookie */
+#define GMON_VERSION	1	/* version number */
+
+/*
+ * Raw header as it appears on file (without padding):
+ */
+struct gmon_hdr {
+    char	cookie[4];
+    char	version[4];
+    char	spare[3*4];
+};
+
+/* types of records in this file: */
+typedef enum {
+    GMON_TAG_TIME_HIST, GMON_TAG_CG_ARC, GMON_TAG_BB_COUNT
+} GMON_Record_Tag;
+
+struct gmon_hist_hdr {
+    char low_pc[sizeof(bfd_vma)];	/* base pc address of sample buffer */
+    char high_pc[sizeof(bfd_vma)];	/* max pc address of sampled buffer */
+    char hist_size[4];			/* size of sample buffer */
+    char prof_rate[4];			/* profiling clock rate */
+    char dimen[15];			/* phys. dim., usually "seconds" */
+    char dimen_abbrev;			/* usually 's' for "seconds" */
+};
+
+struct gmon_cg_arc_record {
+    char from_pc[sizeof(bfd_vma)];	/* address within caller's body */
+    char self_pc[sizeof(bfd_vma)];	/* address within callee's body */
+    char count[4];			/* number of arc traversals */
+};
+
+#endif /* gmon_out_h */