[SystemZ] Support all TLS access models - MC part

The current SystemZ back-end only supports the local-exec TLS access model.
This patch adds all required MC support for the other TLS models, which
means in particular:

- Support additional relocation types for
  Initial-exec model: R_390_TLS_IEENT
  Local-dynamic-model: R_390_TLS_LDO32, R_390_TLS_LDO64,
                       R_390_TLS_LDM32, R_390_TLS_LDM64, R_390_TLS_LDCALL
  General-dynamic model: R_390_TLS_GD32, R_390_TLS_GD64, R_390_TLS_GDCALL

- Support assembler syntax to generate additional relocations
  for use with __tls_get_offset calls:
    :tls_gdcall:
    :tls_ldcall:

The patch also adds a new test to verify fixups and relocations,
and removes the (already unused) FK_390_PLT16DBL/FK_390_PLT32DBL
fixup kinds.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229652 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/SystemZ/InstPrinter/SystemZInstPrinter.cpp

@@ -10,6 +10,7 @@
 #include "SystemZInstPrinter.h"
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCSymbol.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;
@@ -124,6 +125,29 @@ void SystemZInstPrinter::printPCRelOperand(const MCInst *MI, int OpNum,
     O << *MO.getExpr();
 }
 
+void SystemZInstPrinter::printPCRelTLSOperand(const MCInst *MI, int OpNum,
+                                              raw_ostream &O) {
+  // Output the PC-relative operand.
+  printPCRelOperand(MI, OpNum, O);
+
+  // Output the TLS marker if present.
+  if ((unsigned)OpNum + 1 < MI->getNumOperands()) {
+    const MCOperand &MO = MI->getOperand(OpNum + 1);
+    const MCSymbolRefExpr &refExp = cast<MCSymbolRefExpr>(*MO.getExpr());
+    switch (refExp.getKind()) {
+      case MCSymbolRefExpr::VK_TLSGD:
+        O << ":tls_gdcall:";
+        break;
+      case MCSymbolRefExpr::VK_TLSLDM:
+        O << ":tls_ldcall:";
+        break;
+      default:
+        llvm_unreachable("Unexpected symbol kind");
+    }
+    O << refExp.getSymbol().getName();
+  }
+}
+
 void SystemZInstPrinter::printOperand(const MCInst *MI, int OpNum,
                                       raw_ostream &O) {
   printOperand(MI->getOperand(OpNum), O);