From 6e37e4a3902188ec41c4be05b2f0f0e324afc0cf Mon Sep 17 00:00:00 2001
From: Julian Seward <jseward@acm.org>
Date: Fri, 27 Feb 2015 10:24:07 +0100
Subject: [PATCH] Bug 1132953 - Zero AsmJSModule::CodeRange and
 AsmJSModule::ExportedFunction::pod on construction, to avoid Valgrind
 warnings.  r=luke.

--HG--
extra : rebase_source : 5dc08d0bd705aca6fbdae6a0a3d208321dcadb9f
---
 js/src/asmjs/AsmJSModule.cpp | 17 ++++++++++++++---
 js/src/asmjs/AsmJSModule.h   |  3 +++
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/js/src/asmjs/AsmJSModule.cpp b/js/src/asmjs/AsmJSModule.cpp
index 74a8c9da810b..a2299d44bc4f 100644
--- a/js/src/asmjs/AsmJSModule.cpp
+++ b/js/src/asmjs/AsmJSModule.cpp
@@ -1304,6 +1304,7 @@ AsmJSModule::CodeRange::CodeRange(uint32_t nameIndex, uint32_t lineNumber,
     profilingReturn_(l.profilingReturn.offset()),
     end_(l.end.offset())
 {
+    PodZero(&u);  // zero padding for Valgrind
     u.kind_ = Function;
     setDeltas(l.entry.offset(), l.profilingJump.offset(), l.profilingEpilogue.offset());
 
@@ -1328,9 +1329,13 @@ AsmJSModule::CodeRange::setDeltas(uint32_t entry, uint32_t profilingJump, uint32
 }
 
 AsmJSModule::CodeRange::CodeRange(Kind kind, uint32_t begin, uint32_t end)
-  : begin_(begin),
+  : nameIndex_(0),
+    lineNumber_(0),
+    begin_(begin),
+    profilingReturn_(0),
     end_(end)
 {
+    PodZero(&u);  // zero padding for Valgrind
     u.kind_ = kind;
 
     MOZ_ASSERT(begin_ <= end_);
@@ -1338,10 +1343,13 @@ AsmJSModule::CodeRange::CodeRange(Kind kind, uint32_t begin, uint32_t end)
 }
 
 AsmJSModule::CodeRange::CodeRange(Kind kind, uint32_t begin, uint32_t profilingReturn, uint32_t end)
-  : begin_(begin),
+  : nameIndex_(0),
+    lineNumber_(0),
+    begin_(begin),
     profilingReturn_(profilingReturn),
     end_(end)
 {
+    PodZero(&u);  // zero padding for Valgrind
     u.kind_ = kind;
 
     MOZ_ASSERT(begin_ < profilingReturn_);
@@ -1351,10 +1359,13 @@ AsmJSModule::CodeRange::CodeRange(Kind kind, uint32_t begin, uint32_t profilingR
 
 AsmJSModule::CodeRange::CodeRange(AsmJSExit::BuiltinKind builtin, uint32_t begin,
                                   uint32_t profilingReturn, uint32_t end)
-  : begin_(begin),
+  : nameIndex_(0),
+    lineNumber_(0),
+    begin_(begin),
     profilingReturn_(profilingReturn),
     end_(end)
 {
+    PodZero(&u);  // zero padding for Valgrind
     u.kind_ = Thunk;
     u.thunk.target_ = builtin;
 
diff --git a/js/src/asmjs/AsmJSModule.h b/js/src/asmjs/AsmJSModule.h
index 2b95355f0cdf..6d51d8496658 100644
--- a/js/src/asmjs/AsmJSModule.h
+++ b/js/src/asmjs/AsmJSModule.h
@@ -453,6 +453,7 @@ class AsmJSModule
             name_ = name;
             maybeFieldName_ = maybeFieldName;
             argCoercions_ = mozilla::Move(argCoercions);
+            mozilla::PodZero(&pod);  // zero padding for Valgrind
             pod.isChangeHeap_ = false;
             pod.returnType_ = returnType;
             pod.codeOffset_ = UINT32_MAX;
@@ -468,6 +469,7 @@ class AsmJSModule
             MOZ_ASSERT_IF(maybeFieldName, maybeFieldName->isTenured());
             name_ = name;
             maybeFieldName_ = maybeFieldName;
+            mozilla::PodZero(&pod);  // zero padding for Valgrind
             pod.isChangeHeap_ = true;
             pod.startOffsetInModule_ = startOffsetInModule;
             pod.endOffsetInModule_ = endOffsetInModule;
@@ -485,6 +487,7 @@ class AsmJSModule
             name_ = rhs.name_;
             maybeFieldName_ = rhs.maybeFieldName_;
             argCoercions_ = mozilla::Move(rhs.argCoercions_);
+            mozilla::PodZero(&pod);  // zero padding for Valgrind
             pod = rhs.pod;
         }