[SystemZ] Define the call instructions as pseudo aliases.

Similar to r191364, but for calls.  This patch also removes the shortening
of BRASL to BRAS within a TU.  Doing that was a bit controversial internally,
since there's a strong expectation with the z assembler that WYWIWYG.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191366 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 9 insertions, 42 deletions

diff --git a/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp b/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp
index 11b520da91..26a8faeea1 100644
--- a/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp
+++ b/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp
@@ -35,15 +35,6 @@ static uint64_t extractBitsForFixup(MCFixupKind Kind, uint64_t Value) {
   llvm_unreachable("Unknown fixup kind!");
 }
 
-// If Opcode is a relaxable interprocedural reference, return the relaxed form,
-// otherwise return 0.
-static unsigned getRelaxedOpcode(unsigned Opcode) {
-  switch (Opcode) {
-  case SystemZ::BRAS: return SystemZ::BRASL;
-  }
-  return 0;
-}
-
 namespace {
 class SystemZMCAsmBackend : public MCAsmBackend {
   uint8_t OSABI;
@@ -59,14 +50,20 @@ public:
     LLVM_OVERRIDE;
   virtual void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
                           uint64_t Value) const LLVM_OVERRIDE;
-  virtual bool mayNeedRelaxation(const MCInst &Inst) const LLVM_OVERRIDE;
+  virtual bool mayNeedRelaxation(const MCInst &Inst) const LLVM_OVERRIDE {
+    return false;
+  }
   virtual bool fixupNeedsRelaxation(const MCFixup &Fixup,
                                     uint64_t Value,
                                     const MCRelaxableFragment *Fragment,
                                     const MCAsmLayout &Layout) const
-    LLVM_OVERRIDE;
+    LLVM_OVERRIDE {
+    return false;
+  }
   virtual void relaxInstruction(const MCInst &Inst,
-                                MCInst &Res) const LLVM_OVERRIDE;
+                                MCInst &Res) const LLVM_OVERRIDE {
+    llvm_unreachable("SystemZ does do not have assembler relaxation");
+  }
   virtual bool writeNopData(uint64_t Count,
                             MCObjectWriter *OW) const LLVM_OVERRIDE;
   virtual MCObjectWriter *createObjectWriter(raw_ostream &OS) const
@@ -114,28 +111,6 @@ void SystemZMCAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
   }
 }
 
-bool SystemZMCAsmBackend::mayNeedRelaxation(const MCInst &Inst) const {
-  return getRelaxedOpcode(Inst.getOpcode()) != 0;
-}
-
-bool
-SystemZMCAsmBackend::fixupNeedsRelaxation(const MCFixup &Fixup,
-                                          uint64_t Value,
-                                          const MCRelaxableFragment *Fragment,
-                                          const MCAsmLayout &Layout) const {
-  // At the moment we just need to relax 16-bit fields to wider fields.
-  Value = extractBitsForFixup(Fixup.getKind(), Value);
-  return (int16_t)Value != (int64_t)Value;
-}
-
-void SystemZMCAsmBackend::relaxInstruction(const MCInst &Inst,
-                                           MCInst &Res) const {
-  unsigned Opcode = getRelaxedOpcode(Inst.getOpcode());
-  assert(Opcode && "Unexpected insn to relax");
-  Res = Inst;
-  Res.setOpcode(Opcode);
-}
-
 bool SystemZMCAsmBackend::writeNopData(uint64_t Count,
                                        MCObjectWriter *OW) const {
   for (uint64_t I = 0; I != Count; ++I)
diff --git a/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp b/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
index bda771452f..f07ea7b31e 100644
--- a/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
+++ b/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
@@ -79,14 +79,6 @@ private:
                               SmallVectorImpl<MCFixup> &Fixups) const {
     return getPCRelEncoding(MI, OpNum, Fixups, SystemZ::FK_390_PC32DBL, 2);
   }
-  uint64_t getPLT16DBLEncoding(const MCInst &MI, unsigned OpNum,
-                               SmallVectorImpl<MCFixup> &Fixups) const {
-    return getPCRelEncoding(MI, OpNum, Fixups, SystemZ::FK_390_PLT16DBL, 2);
-  }
-  uint64_t getPLT32DBLEncoding(const MCInst &MI, unsigned OpNum,
-                               SmallVectorImpl<MCFixup> &Fixups) const {
-    return getPCRelEncoding(MI, OpNum, Fixups, SystemZ::FK_390_PLT32DBL, 2);
-  }
 };
 }