Add an OtherPreserved field to the CalleeSaved TableGen class.

This field specifies registers that are preserved across function calls,
but that should not be included in the generates SaveList array.

This can be used ot generate regmasks for architectures that save
registers through other means, like SPARC's register windows.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189084 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 1 deletions

diff --git a/utils/TableGen/RegisterInfoEmitter.cpp b/utils/TableGen/RegisterInfoEmitter.cpp
index 731dccf75e..9a30e159be 100644
--- a/utils/TableGen/RegisterInfoEmitter.cpp
+++ b/utils/TableGen/RegisterInfoEmitter.cpp
@@ -1314,9 +1314,21 @@ RegisterInfoEmitter::runTargetDesc(raw_ostream &OS, CodeGenTarget &Target,
     OS << "0 };\n";
 
     // Emit the *_RegMask bit mask of call-preserved registers.
+    BitVector Covered = RegBank.computeCoveredRegisters(*Regs);
+
+    // Check for an optional OtherPreserved set.
+    // Add those registers to RegMask, but not to SaveList.
+    if (DagInit *OPDag =
+        dyn_cast<DagInit>(CSRSet->getValueInit("OtherPreserved"))) {
+      SetTheory::RecSet OPSet;
+      RegBank.getSets().evaluate(OPDag, OPSet, CSRSet->getLoc());
+      Covered |= RegBank.computeCoveredRegisters(
+        ArrayRef<Record*>(OPSet.begin(), OPSet.end()));
+    }
+
     OS << "static const uint32_t " << CSRSet->getName()
        << "_RegMask[] = { ";
-    printBitVectorAsHex(OS, RegBank.computeCoveredRegisters(*Regs), 32);
+    printBitVectorAsHex(OS, Covered, 32);
     OS << "};\n";
   }
   OS << "\n\n";