From 99a50b2bb51f542cb31fee4656580a165f95a57d Mon Sep 17 00:00:00 2001
From: Nicky <sl.nicky.ml@googlemail.com>
Date: Mon, 27 Apr 2020 13:32:14 +0200
Subject: [PATCH] Linux; FIRE-29492: completely disable cacheOptimize again.

---
 indra/llmath/llvolume.cpp | 44 ++++-----------------------------------
 1 file changed, 4 insertions(+), 40 deletions(-)

diff --git a/indra/llmath/llvolume.cpp b/indra/llmath/llvolume.cpp
index c9b3f1d1b5..77f142659b 100644
--- a/indra/llmath/llvolume.cpp
+++ b/indra/llmath/llvolume.cpp
@@ -5295,21 +5295,14 @@ bool LLVolumeFace::cacheOptimize()
 	llassert(!mOptimized);
 	mOptimized = TRUE;
 
-	// <FS:ND> FIRE-23370/BUG-8801/MAIN-5060
+	// <FS:ND> FIRE-23370/BUG-8801/MAIN-5060/FIRE-29492
 	// cacheOptimize will destroy triangles. This is due to LLVCacheVertexData pointing to vertices in the vector vertex_data.
 	// Once vertex_data is sorted (std::sort(triangle_data.begin(), triangle_data.end()) ) this will invalidate those pointers and
 	// LLVCacheVertexData suddenly does point to unrelated vertices. It is an interesting fact that this is no problem for the
 	// windows version.
 	//
-	// To solve the issue with the pointer invalidation it use a std::vector< U16 > for triangle indices, sort this using
-	// std::sort( v.begin(), v.end(), [&triangle_data](U16 rhs, U16 lhs ){ return triangle_data[rhs].mScore > triangle_data[lhs].mScore; }
-	// Then access all LLVCacheTriangleData> via triangle_data[ v[ idx ] ].
-	//
-	// Unfortunately this is a bit of a messy interwoven change all of this method, alternative is to copy a Linux specific version. Which
-	// won't be that great either
-	// NB The change really should be safe for Winows too, in fact it is surprising Windows does not suffer fro the sae bug. Just cannot test
-	// the windows versions right now.
 	
+#ifndef LL_LINUX
 	LLVCacheLRU cache;
 	
 	if (mNumVertices < 3 || mNumIndices < 3)
@@ -5344,13 +5337,6 @@ bool LLVolumeFace::cacheOptimize()
 		triangle_data[tri_idx].mVertex[i%3] = &(vertex_data[idx]);
 	}
 
-// <FS:ND> FIRE-23370/BUG-8801/MAIN-5060
-#ifdef LL_LINUX
-	std::vector< U32 > v;
-	for (U32 j = 0; j < triangle_data.size(); ++j)
-		v.push_back( j );
-#endif
-	
 	/*F32 pre_acmr = 1.f;
 	//measure cache misses from before rebuild
 	{
@@ -5382,27 +5368,14 @@ bool LLVolumeFace::cacheOptimize()
 	}
 
 	//sort triangle data by score
-// <FS:ND> FIRE-23370/BUG-8801/MAIN-5060
-#ifndef LL_LINUX
 	std::sort(triangle_data.begin(), triangle_data.end());
-#else
-	std::sort( v.begin(), v.end(),
-			   [&triangle_data](U16 rhs, U16 lhs )
-			   { return triangle_data[rhs].mScore > triangle_data[lhs].mScore; }
-			   );
-#endif
 		
 	std::vector<U16> new_indices;
 
 	LLVCacheTriangleData* tri;
 
 	//prime pump by adding first triangle to cache;
-// <FS:ND> FIRE-23370/BUG-8801/MAIN-5060
-#ifndef LL_LINUX
 	tri = &(triangle_data[0]);
-#else
-	tri = &(triangle_data[v[0]]);
-#endif
 	
 	cache.addTriangle(tri);
 	new_indices.push_back(tri->mVertex[0]->mIdx);
@@ -5420,21 +5393,11 @@ bool LLVolumeFace::cacheOptimize()
 			breaks++;
 			for (U32 j = 0; j < triangle_data.size(); ++j)
 			{
-// <FS:ND> FIRE-23370/BUG-8801/MAIN-5060
-#ifndef LL_LINUX
 				if (triangle_data[j].mActive)
 				{
 					tri = &(triangle_data[j]);
 					break;
 				}
-#else
-				if (triangle_data[v[j]].mActive)
-				{
-					tri = &(triangle_data[v[j]]);
-					break;
-				}
-#endif
-
 			}
 		}	
 		
@@ -5565,7 +5528,8 @@ bool LLVolumeFace::cacheOptimize()
 
 	//std::string result = llformat("ACMR pre/post: %.3f/%.3f  --  %d triangles %d breaks", pre_acmr, post_acmr, mNumIndices/3, breaks);
 	//LL_INFOS() << result << LL_ENDL;
-
+#endif
+	
 	return true;
 }