[JITLink][COFF] Use DLLImportDefinitionGenerator for creating PLT stubs.

Uses DLLImportDefinitionGenerator for creating PLT stubs. It removes previous approach for dllimport stub creation which can't deal with jump thunks. Reviewed By: lhames Differential Revision: https://reviews.llvm.org/D132524
llvm · Sep 10, 2022 · bc24e6a · bc24e6a
1 parent 545affb
commit bc24e6a
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Showing 5 changed files with 6 additions and 37 deletions.
diff --git a/llvm/lib/ExecutionEngine/JITLink/COFFLinkGraphBuilder.cpp b/llvm/lib/ExecutionEngine/JITLink/COFFLinkGraphBuilder.cpp
@@ -227,17 +227,7 @@ Error COFFLinkGraphBuilder::graphifySymbols() {
                << " (index: " << SectionIndex << ") \n";
       });
     else if (Sym->isUndefined()) {
-      if (SymbolName.startswith(getDLLImportStubPrefix())) {
-        if (Sym->getValue() != 0)
-          return make_error<JITLinkError>(
-              "DLL import symbol has non-zero offset");
-
-        auto ExternalSym = createExternalSymbol(
-            SymIndex, SymbolName.drop_front(getDLLImportStubPrefix().size()),
-            *Sym, Sec);
-        GSym = &createDLLImportEntry(SymbolName, *ExternalSym);
-      } else
-        GSym = createExternalSymbol(SymIndex, SymbolName, *Sym, Sec);
+      GSym = createExternalSymbol(SymIndex, SymbolName, *Sym, Sec);
     } else if (Sym->isWeakExternal()) {
       auto *WeakExternal = Sym->getAux<object::coff_aux_weak_external>();
       COFFSymbolIndex TagIndex = WeakExternal->TagIndex;

diff --git a/llvm/lib/ExecutionEngine/JITLink/COFFLinkGraphBuilder.h b/llvm/lib/ExecutionEngine/JITLink/COFFLinkGraphBuilder.h
@@ -46,7 +46,6 @@ class COFFLinkGraphBuilder {
   const object::COFFObjectFile &getObject() const { return Obj; }
 
   virtual Error addRelocations() = 0;
-  virtual Symbol &createDLLImportEntry(StringRef StubName, Symbol &Target) = 0;
 
   Error graphifySections();
   Error graphifySymbols();

diff --git a/llvm/lib/ExecutionEngine/JITLink/COFF_x86_64.cpp b/llvm/lib/ExecutionEngine/JITLink/COFF_x86_64.cpp
@@ -62,12 +62,6 @@ class COFFLinkGraphBuilder_x86_64 : public COFFLinkGraphBuilder {
     return Error::success();
   }
 
-  Symbol &createDLLImportEntry(StringRef StubName, Symbol &Target) override {
-    auto &Sym = DLLImportTable.getEntryForTarget(getGraph(), Target);
-    Sym.setName(StubName);
-    return Sym;
-  }
-
   Error addSingleRelocation(const object::RelocationRef &Rel,
                             const object::SectionRef &FixupSect,
                             Block &BlockToFix) {
@@ -186,8 +180,6 @@ class COFFLinkGraphBuilder_x86_64 : public COFFLinkGraphBuilder {
     return Error::success();
   }
 
-  x86_64::GOTTableManager DLLImportTable;
-
 public:
   COFFLinkGraphBuilder_x86_64(const object::COFFObjectFile &Obj, const Triple T)
       : COFFLinkGraphBuilder(Obj, std::move(T), getCOFFX86RelocationKindName) {}

diff --git a/llvm/lib/ExecutionEngine/Orc/COFFPlatform.cpp b/llvm/lib/ExecutionEngine/Orc/COFFPlatform.cpp
@@ -180,8 +180,10 @@ COFFPlatform::Create(ExecutionSession &ES, ObjectLinkingLayer &ObjLinkingLayer,
   if (auto Err = PlatformJD.define(symbolAliases(std::move(*RuntimeAliases))))
     return std::move(Err);
 
+  auto &HostFuncJD = ES.createBareJITDylib("$<PlatformRuntimeHostFuncJD>");
+
   // Add JIT-dispatch function support symbols.
-  if (auto Err = PlatformJD.define(absoluteSymbols(
+  if (auto Err = HostFuncJD.define(absoluteSymbols(
           {{ES.intern("__orc_rt_jit_dispatch"),
             {EPC.getJITDispatchInfo().JITDispatchFunction.getValue(),
              JITSymbolFlags::Exported}},
@@ -195,6 +197,7 @@ COFFPlatform::Create(ExecutionSession &ES, ObjectLinkingLayer &ObjLinkingLayer,
       StaticLibraryDefinitionGenerator::Load(ObjLinkingLayer, OrcRuntimePath);
   if (!OrcRuntimeArchiveGenerator)
     return OrcRuntimeArchiveGenerator.takeError();
+  PlatformJD.addToLinkOrder(HostFuncJD);
 
   // Create the instance.
   Error Err = Error::success();
@@ -225,6 +228,7 @@ Error COFFPlatform::setupJITDylib(JITDylib &JD) {
       return Err;
   }
 
+  JD.addGenerator(DLLImportDefinitionGenerator::Create(ES, ObjLinkingLayer));
   return Error::success();
 }
 

diff --git a/llvm/test/ExecutionEngine/JITLink/X86/COFF_x86-64_small_pic_relocations.s b/llvm/test/ExecutionEngine/JITLink/X86/COFF_x86-64_small_pic_relocations.s
@@ -4,7 +4,6 @@
 # RUN: llvm-jitlink -noexec \
 # RUN:              -slab-allocate 100Kb -slab-address 0xfff00000 -slab-page-size 4096 \
 # RUN:              -abs external_data=0xdeadbeef \
-# RUN:              -abs extern_out_of_range32=0x7fff00000000 \
 # RUN:              -check %s %t/coff_sm_reloc.o
 
 	.text
@@ -40,21 +39,6 @@ test_rel32_func:
 test_rel32_data:
     leaq named_data(%rip), %rax
 
-# Check a dllimport stub for target out of reach is created as a GOT entry.
-# jitlink-check: decode_operand(test_call_dllimport, 3) = \
-# jitlink-check:     got_addr(coff_sm_reloc.o, extern_out_of_range32) - \
-# jitlink-check:        next_pc(test_call_dllimport)
-# jitlink-check: *{8}(got_addr(coff_sm_reloc.o, extern_out_of_range32)) = \
-# jitlink-check:     extern_out_of_range32
-	.def test_call_dllimport;
-	.scl 2;
-	.type 32;
-	.endef
-	.globl test_call_dllimport
-	.p2align 4, 0x90
-test_call_dllimport:
-	callq	*__imp_extern_out_of_range32(%rip)
-
 # Check IMAGE_REL_AMD64_ADDR64 sets address of symbol to the fixup position.
 # jitlink-check: *{8}(test_addr64) = named_data
 	.text