Fix Julia JIT integration on Windows x86_64 (#394)

Author: maleadt

src/core/module.jl

@@ -1,10 +1,10 @@
 # Modules represent the top-level structure in an LLVM program.
 
-export dispose,
+export dispose, context,
        name, name!,
        triple, triple!,
        datalayout, datalayout!,
-       context, inline_asm!,
+       inline_asm, inline_asm!,
        set_used!, set_compiler_used!
 
 # forward definition of Module in src/core/value/constant.jl
@@ -64,8 +64,19 @@ datalayout!(mod::Module, layout::String) = API.LLVMSetDataLayout(mod, layout)
 datalayout!(mod::Module, layout::DataLayout) =
     API.LLVMSetModuleDataLayout(mod, layout)
 
-inline_asm!(mod::Module, asm::String) =
-    API.LLVMSetModuleInlineAsm(mod, asm)
+function inline_asm!(mod::Module, asm::String; overwrite::Bool=false)
+    if overwrite
+        API.LLVMSetModuleInlineAsm2(mod, asm, length(asm))
+    else
+        API.LLVMAppendModuleInlineAsm(mod, asm, length(asm))
+    end
+end
+
+function inline_asm(mod::Module)
+    out_len = Ref{Csize_t}()
+    ptr = convert(Ptr{UInt8}, API.LLVMGetModuleInlineAsm(mod, out_len))
+    return unsafe_string(ptr, out_len[])
+end
 
 context(mod::Module) = Context(API.LLVMGetModuleContext(mod))
 

src/orc.jl

@@ -400,8 +400,32 @@ function add!(jljit::JuliaOJIT, jd::JITDylib, obj::MemoryBuffer)
     return nothing
 end
 
-function add!(jljit::JuliaOJIT, jd::JITDylib, mod::ThreadSafeModule)
-    @check API.JLJITAddLLVMIRModule(jljit, jd, mod)
+function decorate_module(mod)
+    # TODO: check the triple, not the system
+    if Sys.iswindows() && Sys.ARCH == :x86_64 &&
+       !contains(inline_asm(mod), "__UnwindData")
+        inline_asm!(mod, """
+            .section .text
+            .type   __UnwindData,@object
+            .p2align        2, 0x90
+            __UnwindData:
+                .zero   12
+                .size   __UnwindData, 12
+
+                .type   __catchjmp,@object
+                .p2align        2, 0x90
+            __catchjmp:
+                .zero   12
+                .size   __catchjmp, 12""")
+    end
+end
+
+function add!(jljit::JuliaOJIT, jd::JITDylib, tsm::ThreadSafeModule)
+    # Julia's debug info expects certain symbols to be present
+    tsm() do mod
+        decorate_module(mod)
+    end
+    @check API.JLJITAddLLVMIRModule(jljit, jd, tsm)
     return nothing
 end
 
@@ -413,17 +437,24 @@ end
 
 @checked struct IRCompileLayer
     ref::API.LLVMOrcIRCompileLayerRef
+    jit
 end
 
 Base.unsafe_convert(::Type{API.LLVMOrcIRCompileLayerRef}, il::IRCompileLayer) = il.ref
 
 function emit(il::IRCompileLayer, mr::MaterializationResponsibility, tsm::ThreadSafeModule)
+    if il.jit isa JuliaOJIT
+        # Julia's debug info expects certain symbols to be present
+        tsm() do mod
+            decorate_module(mod)
+        end
+    end
     API.LLVMOrcIRCompileLayerEmit(il, mr, tsm)
 end
 
 function IRCompileLayer(jljit::JuliaOJIT)
     ref = API.JLJITGetIRCompileLayer(jljit)
-    IRCompileLayer(ref)
+    IRCompileLayer(ref, jljit)
 end
 
 export JuliaOJIT

test/core_tests.jl

@@ -1032,7 +1032,11 @@ end
     show(devnull, mod)
 
     inline_asm!(mod, "nop")
-    @test occursin("module asm", string(mod))
+    @test split(inline_asm(mod)) == ["nop"]
+    inline_asm!(mod, "nop")
+    @test split(inline_asm(mod)) == ["nop", "nop"]
+    inline_asm!(mod, "nop"; overwrite=true)
+    @test split(inline_asm(mod)) == ["nop"]
 
     dummyTriple = "SomeTriple"
     triple!(mod, dummyTriple)