[llvm] r268393 - Provide some default values for the ThinLTO Cache pruning

[Mehdi Amini via llvm-commits]

Author: mehdi_amini
Date: Tue May  3 10:17:50 2016
New Revision: 268393

URL: http://llvm.org/viewvc/llvm-project?rev=268393&view=rev
Log:
Provide some default values for the ThinLTO Cache pruning

This control how the cache is pruned. The cache still has to
be explicitely enabled/disabled by providing a path.

From: Mehdi Amini <mehdi.amini at apple.com>

Modified:
    llvm/trunk/include/llvm-c/lto.h
    llvm/trunk/include/llvm/LTO/ThinLTOCodeGenerator.h

Modified: llvm/trunk/include/llvm-c/lto.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm-c/lto.h?rev=268393&r1=268392&r2=268393&view=diff
==============================================================================
--- llvm/trunk/include/llvm-c/lto.h (original)
+++ llvm/trunk/include/llvm-c/lto.h Tue May  3 10:17:50 2016
@@ -659,6 +659,7 @@ extern lto_bool_t thinlto_codegen_set_pi
 
 /**
  * Sets the path to a directory to use as a cache storage for incremental build.
+ * Setting this activates caching.
  *
  * \since LTO_API_VERSION=18
  */
@@ -667,7 +668,7 @@ extern void thinlto_codegen_set_cache_di
 
 /**
  * Sets the cache pruning interval (in seconds). A negative value disable the
- * pruning (default).
+ * pruning. An unspecified default value will be applied.
  *
  * \since LTO_API_VERSION=18
  */
@@ -678,7 +679,8 @@ extern void thinlto_codegen_set_cache_pr
  * Sets the maximum cache size that can be persistent across build, in terms of
  * percentage of the available space on the the disk. Set to 100 to indicate
  * no limit, 50 to indicate that the cache size will not be left over half the
- * available space. A value over 100 will be reduced to 100.
+ * available space. A value over 100 will be reduced to 100. An unspecified 
+ * default value will be applied.
  *
  * The formula looks like:
  *  AvailableSpace = FreeSpace + ExistingCacheSize
@@ -690,7 +692,8 @@ extern void thinlto_codegen_set_final_ca
     thinlto_code_gen_t cg, unsigned percentage);
 
 /**
- * Sets the expiration (in seconds) for an entry in the cache.
+ * Sets the expiration (in seconds) for an entry in the cache. An unspecified
+ * default value will be applied.
  *
  * \since LTO_API_VERSION=18
  */

Modified: llvm/trunk/include/llvm/LTO/ThinLTOCodeGenerator.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/LTO/ThinLTOCodeGenerator.h?rev=268393&r1=268392&r2=268393&view=diff
==============================================================================
--- llvm/trunk/include/llvm/LTO/ThinLTOCodeGenerator.h (original)
+++ llvm/trunk/include/llvm/LTO/ThinLTOCodeGenerator.h Tue May  3 10:17:50 2016
@@ -108,10 +108,10 @@ public:
    */
 
   struct CachingOptions {
-    std::string Path;
-    int PruningInterval = -1;               // seconds, -1 to disable pruning
-    unsigned int Expiration = 0;            // seconds.
-    unsigned MaxPercentageOfAvailableSpace = 0; // percentage.
+    std::string Path;                    // Path to the cache, empty to disable.
+    int PruningInterval = 1200;          // seconds, -1 to disable pruning.
+    unsigned int Expiration = 7 * 24 * 3600;     // seconds (1w default).
+    unsigned MaxPercentageOfAvailableSpace = 75; // percentage.
   };
 
   /// Provide a path to a directory where to store the cached files for