1 files changed, 48 insertions, 4 deletions

diff --git a/contrib/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp b/contrib/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp
index 99ea2fa..b73af82 100644
--- a/contrib/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp
+++ b/contrib/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp
@@ -13,7 +13,9 @@
 #include "MCTargetDesc/HexagonBaseInfo.h"
 #include "MCTargetDesc/HexagonMCInstrInfo.h"
 #include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAsmLayout.h"
 #include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCELFObjectWriter.h"
 #include "llvm/MC/MCFixupKindInfo.h"
 #include "llvm/MC/MCInstrInfo.h"
@@ -33,14 +35,28 @@ class HexagonAsmBackend : public MCAsmBackend {
   mutable uint64_t relaxedCnt;
   std::unique_ptr <MCInstrInfo> MCII;
   std::unique_ptr <MCInst *> RelaxTarget;
+  MCInst * Extender;
 public:
   HexagonAsmBackend(Target const &T,  uint8_t OSABI, StringRef CPU) :
-    OSABI(OSABI), MCII (T.createMCInstrInfo()), RelaxTarget(new MCInst *){}
+    OSABI(OSABI), MCII (T.createMCInstrInfo()), RelaxTarget(new MCInst *),
+    Extender(nullptr) {}
 
   MCObjectWriter *createObjectWriter(raw_pwrite_stream &OS) const override {
     return createHexagonELFObjectWriter(OS, OSABI, CPU);
   }
 
+  void setExtender(MCContext &Context) const {
+    if (Extender == nullptr)
+      const_cast<HexagonAsmBackend *>(this)->Extender = new (Context) MCInst;
+  }
+
+  MCInst *takeExtender() const {
+    assert(Extender != nullptr);
+    MCInst * Result = Extender;
+    const_cast<HexagonAsmBackend *>(this)->Extender = nullptr;
+    return Result;
+  }
+
   unsigned getNumFixupKinds() const override {
     return Hexagon::NumTargetFixupKinds;
   }
@@ -222,6 +238,7 @@ public:
         if (HexagonMCInstrInfo::bundleSize(MCB) < HEXAGON_PACKET_SIZE) {
           ++relaxedCnt;
           *RelaxTarget = &MCI;
+          setExtender(Layout.getAssembler().getContext());
           return true;
         } else {
           return false;
@@ -262,6 +279,7 @@ public:
       if (HexagonMCInstrInfo::bundleSize(MCB) < HEXAGON_PACKET_SIZE) {
         ++relaxedCnt;
         *RelaxTarget = &MCI;
+        setExtender(Layout.getAssembler().getContext());
         return true;
       }
     }
@@ -276,9 +294,35 @@ public:
     llvm_unreachable("Handled by fixupNeedsRelaxationAdvanced");
   }
 
-  void relaxInstruction(MCInst const & /*Inst*/,
-                        MCInst & /*Res*/) const override {
-    llvm_unreachable("relaxInstruction() unimplemented");
+  void relaxInstruction(MCInst const & Inst,
+                        MCInst & Res) const override {
+    assert(HexagonMCInstrInfo::isBundle(Inst) &&
+           "Hexagon relaxInstruction only works on bundles");
+
+    Res = HexagonMCInstrInfo::createBundle();
+    // Copy the results into the bundle.
+    bool Update = false;
+    for (auto &I : HexagonMCInstrInfo::bundleInstructions(Inst)) {
+      MCInst &CrntHMI = const_cast<MCInst &>(*I.getInst());
+
+      // if immediate extender needed, add it in
+      if (*RelaxTarget == &CrntHMI) {
+        Update = true;
+        assert((HexagonMCInstrInfo::bundleSize(Res) < HEXAGON_PACKET_SIZE) &&
+               "No room to insert extender for relaxation");
+
+        MCInst *HMIx = takeExtender();
+        *HMIx = HexagonMCInstrInfo::deriveExtender(
+                *MCII, CrntHMI,
+                HexagonMCInstrInfo::getExtendableOperand(*MCII, CrntHMI));
+        Res.addOperand(MCOperand::createInst(HMIx));
+        *RelaxTarget = nullptr;
+      }
+      // now copy over the original instruction(the one we may have extended)
+      Res.addOperand(MCOperand::createInst(I.getInst()));
+    }
+    (void)Update;
+    assert(Update && "Didn't find relaxation target");
   }
 
   bool writeNopData(uint64_t Count,