From f3374b526619671fe576d593dcdc6bd048bf5603 Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Mon, 21 Apr 2014 22:26:46 +0200
Subject: [PATCH 1/3] x64: Allow building with LUAJIT_USE_SYSMALLOC and
 LUAJIT_USE_VALGRIND.

Valgrind 3.9 killed MAP_32BIT support. Ugh. So now we have to rely on
undocumented behavior where Valgrind always allocates from the bottom
of memory. Alas, such a binary won't run properly without Valgrind.
---
 src/Makefile   | 6 ++++--
 src/lib_aux.c  | 2 +-
 src/lj_state.c | 2 +-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/Makefile b/src/Makefile
index 9551781a..c558003c 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -122,8 +122,10 @@ XCFLAGS=
 #
 # Use the system provided memory allocator (realloc) instead of the
 # bundled memory allocator. This is slower, but sometimes helpful for
-# debugging. It's helpful for Valgrind's memcheck tool, too. This option
-# cannot be enabled on x64, since the built-in allocator is mandatory.
+# debugging. This option cannot be enabled on x64, since realloc usually
+# doesn't return addresses in the right address range.
+# OTOH this option is mandatory for Valgrind's memcheck tool on x64 and
+# the only way to get useful results from it for all other architectures.
 #XCFLAGS+= -DLUAJIT_USE_SYSMALLOC
 #
 # This define is required to run LuaJIT under Valgrind. The Valgrind
diff --git a/src/lib_aux.c b/src/lib_aux.c
index 1b01fe07..e88dc7c2 100644
--- a/src/lib_aux.c
+++ b/src/lib_aux.c
@@ -302,7 +302,7 @@ static int panic(lua_State *L)
 
 #ifdef LUAJIT_USE_SYSMALLOC
 
-#if LJ_64
+#if LJ_64 && !defined(LUAJIT_USE_VALGRIND)
 #error "Must use builtin allocator for 64 bit target"
 #endif
 
diff --git a/src/lj_state.c b/src/lj_state.c
index f972fdce..b9eaef46 100644
--- a/src/lj_state.c
+++ b/src/lj_state.c
@@ -175,7 +175,7 @@ static void close_state(lua_State *L)
     g->allocf(g->allocd, G2GG(g), sizeof(GG_State), 0);
 }
 
-#if LJ_64
+#if LJ_64 && !(defined(LUAJIT_USE_VALGRIND) && defined(LUAJIT_USE_SYSMALLOC))
 lua_State *lj_state_newstate(lua_Alloc f, void *ud)
 #else
 LUA_API lua_State *lua_newstate(lua_Alloc f, void *ud)

From 18309b0a25babe1a7d601d2ee92ce1dba1859ef9 Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Tue, 22 Apr 2014 09:57:39 +0200
Subject: [PATCH 2/3] Prevent adding side traces for stack checks.

---
 src/lj_trace.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/lj_trace.c b/src/lj_trace.c
index 9e5e400f..0f48809d 100644
--- a/src/lj_trace.c
+++ b/src/lj_trace.c
@@ -607,6 +607,7 @@ static TValue *trace_state(lua_State *L, lua_CFunction dummy, void *ud)
       }
       lj_opt_split(J);
       lj_opt_sink(J);
+      if (!J->loopref) J->cur.snap[J->cur.nsnap-1].count = SNAPCOUNT_DONE;
       J->state = LJ_TRACE_ASM;
       break;
 

From 2715fe3aee7c8202b4b5d04748d1c5faa6d8fd9c Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Tue, 22 Apr 2014 11:26:52 +0200
Subject: [PATCH 3/3] Prevent GC estimate miscalculation due to buffer growth.

---
 src/lj_gc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/lj_gc.c b/src/lj_gc.c
index c2bc397d..c856df4d 100644
--- a/src/lj_gc.c
+++ b/src/lj_gc.c
@@ -631,6 +631,8 @@ static size_t gc_onestep(lua_State *L)
   case GCSsweep: {
     MSize old = g->gc.total;
     setmref(g->gc.sweep, gc_sweep(g, mref(g->gc.sweep, GCRef), GCSWEEPMAX));
+    lua_assert(old >= g->gc.total);
+    g->gc.estimate -= old - g->gc.total;
     if (gcref(*mref(g->gc.sweep, GCRef)) == NULL) {
       gc_shrink(g, L);
       if (gcref(g->gc.mmudata)) {  /* Need any finalizations? */
@@ -643,8 +645,6 @@ static size_t gc_onestep(lua_State *L)
 	g->gc.debt = 0;
       }
     }
-    lua_assert(old >= g->gc.total);
-    g->gc.estimate -= old - g->gc.total;
     return GCSWEEPMAX*GCSWEEPCOST;
     }
   case GCSfinalize: