Memory: Move to a normal model of ownership of memory pools, for new/delete.

Addresses step 4 of #976, overlaps #916.

For each pool, now, it is newed, remembered, and freed by the same entity,
rather than having a mix (thread finalize freeing current pool) that could
lead to double freeing of the same pool. It is quite rational and simple now.

This will enable reinstalling process and thread tear down.

glslang/MachineIndependent/PoolAlloc.cpp

@@ -47,6 +47,7 @@ OS_TLSIndex PoolIndex;
 struct TThreadMemoryPools
 {
     TPoolAllocator* threadPoolAllocator; // the current pool
+    TPoolAllocator* initialMemoryPool;   // the original pool owned by this thread (this file), to be freed here as well
 };
 
 // Return the thread-specific pool pointers.
@@ -80,6 +81,8 @@ bool InitializePoolIndex()
     if ((PoolIndex = OS_AllocTLSIndex()) == OS_INVALID_TLS_INDEX)
         return false;
 
+    SetThreadMemoryPools(nullptr);
+
     return true;
 }
 
@@ -95,7 +98,8 @@ void InitializeMemoryPools()
 {
     if (GetThreadMemoryPools() == nullptr) {
         SetThreadMemoryPools(new TThreadMemoryPools());
-        SetThreadPoolAllocator(new TPoolAllocator());
+        GetThreadMemoryPools()->initialMemoryPool = new TPoolAllocator();
+        SetThreadPoolAllocator(GetThreadMemoryPools()->initialMemoryPool);
     }
 }
 
@@ -103,9 +107,10 @@ void InitializeMemoryPools()
 void FreeMemoryPools()
 {
     if (GetThreadMemoryPools() != nullptr) {
-        GetThreadPoolAllocator().popAll();
-        delete &GetThreadPoolAllocator();
+        if (GetThreadMemoryPools()->initialMemoryPool != nullptr)
+            delete GetThreadMemoryPools()->initialMemoryPool;
         delete GetThreadMemoryPools();
+        SetThreadMemoryPools(nullptr);
     }
 }
 

glslang/MachineIndependent/ShaderLang.cpp

@@ -1602,8 +1602,9 @@ public:
 };
 
 TShader::TShader(EShLanguage s)
-    : pool(0), stage(s), lengths(nullptr), stringNames(nullptr), preamble("")
+    : stage(s), lengths(nullptr), stringNames(nullptr), preamble("")
 {
+    pool = new TPoolAllocator;
     infoSink = new TInfoSink;
     compiler = new TDeferredCompiler(stage, *infoSink);
     intermediate = new TIntermediate(s);
@@ -1707,7 +1708,6 @@ bool TShader::parse(const TBuiltInResource* builtInResources, int defaultVersion
     if (! InitThread())
         return false;
 
-    pool = new TPoolAllocator();
     SetThreadPoolAllocator(pool);
     if (! preamble)
         preamble = "";
@@ -1731,7 +1731,6 @@ bool TShader::preprocess(const TBuiltInResource* builtInResources,
     if (! InitThread())
         return false;
 
-    pool = new TPoolAllocator();
     SetThreadPoolAllocator(pool);
     if (! preamble)
         preamble = "";
@@ -1752,8 +1751,9 @@ const char* TShader::getInfoDebugLog()
     return infoSink->debug.c_str();
 }
 
-TProgram::TProgram() : pool(0), reflection(0), ioMapper(nullptr), linked(false)
+TProgram::TProgram() : reflection(0), ioMapper(nullptr), linked(false)
 {
+    pool = new TPoolAllocator;
     infoSink = new TInfoSink;
     for (int s = 0; s < EShLangCount; ++s) {
         intermediate[s] = 0;
@@ -1788,7 +1788,6 @@ bool TProgram::link(EShMessages messages)
 
     bool error = false;
 
-    pool = new TPoolAllocator();
     SetThreadPoolAllocator(pool);
 
     for (int s = 0; s < EShLangCount; ++s) {