Add IR support, ELF section and user documentation for partitioning feature.

The partitioning feature was proposed here:
http://lists.llvm.org/pipermail/llvm-dev/2019-February/130583.html

This is mostly just documentation. The feature itself will be contributed
in subsequent patches.

Differential Revision: https://reviews.llvm.org/D60242

llvm-svn: 361923

1 files changed, 19 insertions, 1 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 412f99d5e62..b23115ba31d 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -2892,7 +2892,8 @@ static void inferDSOLocal(GlobalValue *GV) {
 Error BitcodeReader::parseGlobalVarRecord(ArrayRef<uint64_t> Record) {
   // v1: [pointer type, isconst, initid, linkage, alignment, section,
   // visibility, threadlocal, unnamed_addr, externally_initialized,
-  // dllstorageclass, comdat, attributes, preemption specifier] (name in VST)
+  // dllstorageclass, comdat, attributes, preemption specifier,
+  // partition strtab offset, partition strtab size] (name in VST)
   // v2: [strtab_offset, strtab_size, v1]
   StringRef Name;
   std::tie(Name, Record) = readNameFromStrtab(Record);
@@ -2983,6 +2984,10 @@ Error BitcodeReader::parseGlobalVarRecord(ArrayRef<uint64_t> Record) {
   }
   inferDSOLocal(NewGV);
 
+  // Check whether we have enough values to read a partition name.
+  if (Record.size() > 15)
+    NewGV->setPartition(StringRef(Strtab.data() + Record[14], Record[15]));
+
   return Error::success();
 }
 
@@ -3072,6 +3077,12 @@ Error BitcodeReader::parseFunctionRecord(ArrayRef<uint64_t> Record) {
   }
   inferDSOLocal(Func);
 
+  // Record[16] is the address space number.
+
+  // Check whether we have enough values to read a partition name.
+  if (Record.size() > 18)
+    Func->setPartition(StringRef(Strtab.data() + Record[17], Record[18]));
+
   ValueList.push_back(Func);
 
   // If this is a function with a body, remember the prototype we are
@@ -3149,6 +3160,13 @@ Error BitcodeReader::parseGlobalIndirectSymbolRecord(
     NewGA->setDSOLocal(getDecodedDSOLocal(Record[OpNum++]));
   inferDSOLocal(NewGA);
 
+  // Check whether we have enough values to read a partition name.
+  if (OpNum + 1 < Record.size()) {
+    NewGA->setPartition(
+        StringRef(Strtab.data() + Record[OpNum], Record[OpNum + 1]));
+    OpNum += 2;
+  }
+
   ValueList.push_back(NewGA);
   IndirectSymbolInits.push_back(std::make_pair(NewGA, Val));
   return Error::success();