1 files changed, 36 insertions, 7 deletions

diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
index d4d10e0..3e96bdf 100644
--- a/llvm/lib/MC/MCAssembler.cpp
+++ b/llvm/lib/MC/MCAssembler.cpp
@@ -398,6 +398,10 @@ bool MCAssembler::registerSymbol(const MCSymbol &Symbol) {
   return Changed;
 }
 
+void MCAssembler::addRelocDirective(RelocDirective RD) {
+  relocDirectives.push_back(RD);
+}
+
 /// Write the fragment \p F to the output file.
 static void writeFragment(raw_ostream &OS, const MCAssembler &Asm,
                           const MCFragment &F) {
@@ -695,6 +699,27 @@ void MCAssembler::layout() {
   // helps check whether a PC-relative fixup is fully resolved.
   this->HasFinalLayout = true;
 
+  // Resolve .reloc offsets and add fixups.
+  for (auto &PF : relocDirectives) {
+    MCValue Res;
+    auto &O = PF.Offset;
+    if (!O.evaluateAsValue(Res, *this)) {
+      getContext().reportError(O.getLoc(), ".reloc offset is not relocatable");
+      continue;
+    }
+    auto *Sym = Res.getAddSym();
+    auto *F = Sym ? Sym->getFragment() : nullptr;
+    auto *Sec = F ? F->getParent() : nullptr;
+    if (Res.getSubSym() || !Sec) {
+      getContext().reportError(O.getLoc(),
+                               ".reloc offset is not relative to a section");
+      continue;
+    }
+
+    uint64_t Offset = Sym ? Sym->getOffset() + Res.getConstant() : 0;
+    F->addFixup(MCFixup::create(Offset, PF.Expr, PF.Kind));
+  }
+
   // Evaluate and apply the fixups, generating relocation entries as necessary.
   for (MCSection &Sec : *this) {
     for (MCFragment &F : Sec) {
@@ -710,13 +735,17 @@ void MCAssembler::layout() {
         // In the variable part, fixup offsets are relative to the fixed part's
         // start. Extend the variable contents to the left to account for the
         // fixed part size.
-        Contents = MutableArrayRef(F.getParent()->ContentStorage)
-                       .slice(F.VarContentStart - Contents.size(), F.getSize());
-        for (MCFixup &Fixup : F.getVarFixups()) {
-          uint64_t FixedValue;
-          MCValue Target;
-          evaluateFixup(F, Fixup, Target, FixedValue,
-                        /*RecordReloc=*/true, Contents);
+        auto VarFixups = F.getVarFixups();
+        if (VarFixups.size()) {
+          Contents =
+              MutableArrayRef(F.getParent()->ContentStorage)
+                  .slice(F.VarContentStart - Contents.size(), F.getSize());
+          for (MCFixup &Fixup : VarFixups) {
+            uint64_t FixedValue;
+            MCValue Target;
+            evaluateFixup(F, Fixup, Target, FixedValue,
+                          /*RecordReloc=*/true, Contents);
+          }
         }
       } else if (auto *AF = dyn_cast<MCAlignFragment>(&F)) {
         // For RISC-V linker relaxation, an alignment relocation might be