Index: llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp =================================================================== --- llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp +++ llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp @@ -1456,8 +1456,25 @@ unsigned Priority, const MCSymbol *KeySym, MCSectionCOFF *Default) { - if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) - return Ctx.getAssociativeCOFFSection(Default, KeySym, 0); + if (T.isKnownWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) { + // If the priority is the default, use .CRT$XCU, possibly associative. + if (Priority == 65535) + return Ctx.getAssociativeCOFFSection(Default, KeySym, 0); + + // Otherwise, we need to compute a new section name. Low priorities should + // run earlier. The linker will sort sections ASCII-betically, and we need a + // string that sorts between .CRT$XCA and .CRT$XCU. In the general case, we + // make a name like ".CRT$XCT12345", since that runs before .CRT$XCU. Really + // low priorities need to sort before 'L', since the CRT uses that + // internally, so we use ".CRT$XCA00001" for them. + SmallString<24> Name; + raw_svector_ostream OS(Name); + OS << ".CRT$XC" << (Priority < 200 ? 'A' : 'T') << format("%05u", Priority); + MCSectionCOFF *Sec = Ctx.getCOFFSection( + Name, COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ, + SectionKind::getReadOnly()); + return Ctx.getAssociativeCOFFSection(Sec, KeySym, 0); + } std::string Name = IsCtor ? ".ctors" : ".dtors"; if (Priority != 65535) Index: llvm/test/CodeGen/X86/ctor-priority-coff.ll =================================================================== --- /dev/null +++ llvm/test/CodeGen/X86/ctor-priority-coff.ll @@ -0,0 +1,46 @@ +; RUN: llc < %s | FileCheck %s + +; Check that we come up with appropriate section names that link.exe sorts +; well. + +; CHECK: .section .CRT$XCA00042,"dr" +; CHECK: .p2align 3 +; CHECK: .quad f +; CHECK: .section .CRT$XCT12345,"dr" +; CHECK: .p2align 3 +; CHECK: .quad g + +target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-pc-windows-msvc19.14.26433" + +@str0 = private dso_local unnamed_addr constant [6 x i8] c"later\00", align 1 +@str1 = private dso_local unnamed_addr constant [6 x i8] c"first\00", align 1 +@str2 = private dso_local unnamed_addr constant [5 x i8] c"main\00", align 1 +@llvm.global_ctors = appending global [2 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 12345, void ()* @g, i8* null }, { i32, void ()*, i8* } { i32 42, void ()* @f, i8* null }] + +; Function Attrs: nounwind uwtable +define dso_local void @g() #0 { +entry: + %call = tail call i32 @puts(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @str0, i64 0, i64 0)) + ret void +} + +; Function Attrs: nounwind +declare dso_local i32 @puts(i8* nocapture readonly) local_unnamed_addr #1 + +; Function Attrs: nounwind uwtable +define dso_local void @f() #0 { +entry: + %call = tail call i32 @puts(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @str1, i64 0, i64 0)) + ret void +} + +; Function Attrs: nounwind uwtable +define dso_local i32 @main() local_unnamed_addr #0 { +entry: + %call = tail call i32 @puts(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @str2, i64 0, i64 0)) + ret i32 0 +} + +attributes #0 = { nounwind uwtable } +attributes #1 = { nounwind }