support malloc tracing and replay HEAD master

To test and provide reproducable behavior of different mallocs,
provide an architecture-specific tracing mechanism to write
trace files.  Since these traces, they're compressed by gzip(1)
by default to avoid filling up hard drives of long-lived
daemons.

The compressor can be replaced with zstd or bzip2 via
"trace_compress:zstd" in the comma-delimited MWRAP environment.

The new mwrap-trace-replay command is designed to run with either
jemalloc or glibc malloc to replay trace files.  It can read
uncompressed output via stdin or compressed files via
gzip/zstd/bzip2.

This doesn't work reliably in multi-threaded code, but I have
fragmentation problems in single-threaded code.

1 files changed, 34 insertions, 0 deletions

diff --git a/lib/Devel/Mwrap/trace_struct.h b/lib/Devel/Mwrap/trace_struct.h
new file mode 100644
index 0000000..e5fe622
--- /dev/null
+++ b/lib/Devel/Mwrap/trace_struct.h
@@ -0,0 +1,34 @@
+enum tr_fn {
+        TR_FREE = 0,
+        TR_MEMALIGN = 1,
+        TR_MALLOC = 2,
+        TR_REALLOC = 3,
+        TR_CALLOC = 4,
+};
+static const uintptr_t TR_MASK = 7;
+
+struct tr_memalign {
+        uintptr_t ret;
+        size_t alignment;
+        size_t size;
+};
+
+struct tr_free {
+        uintptr_t ptr;
+};
+
+struct tr_malloc {
+        uintptr_t ret;
+        size_t size;
+};
+
+struct tr_realloc {
+        uintptr_t ret;
+        uintptr_t ptr;
+        size_t size;
+};
+
+struct tr_calloc {
+        uintptr_t ret;
+        size_t size;
+};