[ThinLTO][C-API] Correct api comments

Negative values never disabled the pruning - they simply set high values for the pruning interval.

The behaviour now is that negative values set the maximum pruning interval (which appears to have been the intention from the start) see https://reviews.llvm.org/D41231.

I have adjusted the comments to reflect this, removed any inaccurate statements, and corrected any typos I spotted in the English.

Differential Revision: https://reviews.llvm.org/D41279

llvm-svn: 321078

1 files changed, 9 insertions, 9 deletions

diff --git a/llvm/include/llvm-c/lto.h b/llvm/include/llvm-c/lto.h
index 8d45b783204..0fc02f46f7a 100644
--- a/llvm/include/llvm-c/lto.h
+++ b/llvm/include/llvm-c/lto.h
@@ -757,17 +757,17 @@ extern void thinlto_codegen_add_cross_referenced_symbol(thinlto_code_gen_t cg,
  * @ingroup LLVMCTLTO
  *
  * These entry points control the ThinLTO cache. The cache is intended to
- * support incremental build, and thus needs to be persistent accross build.
- * The client enabled the cache by supplying a path to an existing directory.
+ * support incremental builds, and thus needs to be persistent across builds.
+ * The client enables the cache by supplying a path to an existing directory.
  * The code generator will use this to store objects files that may be reused
  * during a subsequent build.
  * To avoid filling the disk space, a few knobs are provided:
- *  - The pruning interval limit the frequency at which the garbage collector
- *    will try to scan the cache directory to prune it from expired entries.
- *    Setting to -1 disable the pruning (default).
+ *  - The pruning interval limits the frequency at which the garbage collector
+ *    will try to scan the cache directory to prune expired entries.
+ *    Setting to a negative number applies the maximum interval.
  *  - The pruning expiration time indicates to the garbage collector how old an
  *    entry needs to be to be removed.
- *  - Finally, the garbage collector can be instructed to prune the cache till
+ *  - Finally, the garbage collector can be instructed to prune the cache until
  *    the occupied space goes below a threshold.
  * @{
  */
@@ -782,9 +782,9 @@ extern void thinlto_codegen_set_cache_dir(thinlto_code_gen_t cg,
                                           const char *cache_dir);
 
 /**
- * Sets the cache pruning interval (in seconds). A negative value disable the
- * pruning. An unspecified default value will be applied, and a value of 0 will
- * be ignored.
+ * Sets the cache pruning interval (in seconds). A negative value sets the
+ * maximum possible pruning interval. An unspecified default value will be
+ * applied, and a value of 0 will be ignored.
  *
  * \since LTO_API_VERSION=18
  */