From a64ed1a5ee9913df40563878b3b3b61deda8f1eb Mon Sep 17 00:00:00 2001
From: Brendan Eich <brendan@mozilla.org>
Date: Wed, 11 Jun 2008 17:21:15 -0700
Subject: [PATCH] native_pointer_to_jsval should not lose low-order bits (plus
 random style nits).

---
 js/src/jstracer.cpp      |  6 +++---
 js/src/jstracer.h        | 20 ++++++++++++++------
 js/src/jstracerinlines.h |  1 -
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/js/src/jstracer.cpp b/js/src/jstracer.cpp
index 063920916e1..27e1e84a47a 100644
--- a/js/src/jstracer.cpp
+++ b/js/src/jstracer.cpp
@@ -54,18 +54,18 @@ js_GetRecorder(JSContext* cx)
     JSBool ok =
 #endif
     JS_ExecuteScript(cx, JS_GetGlobalObject(cx), script, &result);
-    JS_ASSERT(ok && JSVAL_IS_OBJECT(result));
+    JS_ASSERT(ok && !JSVAL_IS_PRIMITIVE(result));
     return tm->recorder = JSVAL_TO_OBJECT(result);
 }
 
 jsval
-js_CallRecorder(JSContext* cx, const char* fn, uintN argc, jsval* argv)
+js_CallRecorder(JSContext* cx, const char* name, uintN argc, jsval* argv)
 {
     jsval rval;
 #ifdef DEBUG
     JSBool ok =
 #endif
-    JS_CallFunctionName(cx, js_GetRecorder(cx), fn, argc, argv, &rval);
+    JS_CallFunctionName(cx, js_GetRecorder(cx), name, argc, argv, &rval);
     JS_ASSERT(ok);
     return rval;
 }
diff --git a/js/src/jstracer.h b/js/src/jstracer.h
index 2b31e5a9565..375da4b5542 100644
--- a/js/src/jstracer.h
+++ b/js/src/jstracer.h
@@ -60,18 +60,26 @@ struct JSTraceMonitor {
 
 #define TRACE_TRIGGER_MASK 0x3f
 
-jsval js_CallRecorder(JSContext* cx, const char* fn, uintN argc, jsval* argv);
-jsval js_CallRecorder(JSContext* cx, const char* fn, jsval a);
-jsval js_CallRecorder(JSContext* cx, const char* fn, jsval a, jsval b);
+jsval
+js_CallRecorder(JSContext* cx, const char* name, uintN argc, jsval* argv);
+
+jsval
+js_CallRecorder(JSContext* cx, const char* name, jsval a);
+
+jsval
+js_CallRecorder(JSContext* cx, const char* name, jsval a, jsval b);
 
 /*
- * The recorder needs to keep track of native machine addresses. This mapping
- * only works for aligned pointers.
+ * The recorder needs to keep track of native machine addresses, including
+ * bytecode addresses which are currently arbitrarily byte-aligned. Therefore
+ * we cannot use PRIVATE_TO_JSVAL, which assumes at least (0 mod 2) alignment
+ * and unconditionally sets the least significant (JSVAL_INT) bit. Instead, we
+ * risk lopping off the most significant bit (or bits on 64-bit systems).
  */
 static inline jsval
 native_pointer_to_jsval(void* p)
 {
-    return INT_TO_JSVAL(((uint32)p) >> 2);
+    return INT_TO_JSVAL(JS_PTR_TO_UINT32(p));
 }
 
 #endif /* jstracer_h___ */
diff --git a/js/src/jstracerinlines.h b/js/src/jstracerinlines.h
index 482554832df..033477a77f3 100644
--- a/js/src/jstracerinlines.h
+++ b/js/src/jstracerinlines.h
@@ -68,7 +68,6 @@
                             b) != JSVAL_TRUE;                                 \
     JS_END_MACRO
 
-
 static inline void
 prim_push_stack(JSContext* cx, JSFrameRegs& regs, jsval& v)
 {