Decouple dllexport/dllimport from linkage

Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.

Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:

  define available_externally dllimport void @f() {}
  @Var = dllexport global i32 1, align 4

Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.

llvm-svn: 199218

5 files changed, 280 insertions, 20 deletions

diff --git a/llvm/test/CodeGen/X86/dll-linkage.ll b/llvm/test/CodeGen/X86/dll-linkage.ll
deleted file mode 100644
index a0c2a54a99a..00000000000
--- a/llvm/test/CodeGen/X86/dll-linkage.ll
+++ /dev/null
@@ -1,14 +0,0 @@
-; RUN: llc < %s -mtriple=i386-pc-mingw32 | FileCheck %s
-
-; RUN: llc < %s -mtriple=i386-pc-mingw32 -O0 | FileCheck %s -check-prefix=FAST
-; PR6275
-
-declare dllimport void @foo()
-
-define void @bar() nounwind {
-; CHECK: calll	*__imp__foo
-; FAST:  movl   __imp__foo, [[R:%[a-z]{3}]]
-; FAST:  calll  *[[R]]
-  call void @foo()
-  ret void
-}
diff --git a/llvm/test/CodeGen/X86/dllexport-x86_64.ll b/llvm/test/CodeGen/X86/dllexport-x86_64.ll
new file mode 100644
index 00000000000..6bf73aa5366
--- /dev/null
+++ b/llvm/test/CodeGen/X86/dllexport-x86_64.ll
@@ -0,0 +1,79 @@
+; RUN: llc -mtriple x86_64-pc-win32 < %s | FileCheck -check-prefix=CHECK -check-prefix=WIN32 %s
+; RUN: llc -mtriple x86_64-pc-mingw32 < %s | FileCheck -check-prefix=CHECK -check-prefix=MINGW %s
+
+; CHECK: .text
+
+define void @notExported() {
+	ret void
+}
+
+; CHECK: .globl f1
+define dllexport void @f1() {
+	ret void
+}
+
+; CHECK: .globl f2
+define dllexport void @f2() unnamed_addr {
+	ret void
+}
+
+; CHECK: .section .text,"xr",discard,lnk1
+; CHECK: .globl lnk1
+define linkonce_odr dllexport void @lnk1() {
+	ret void
+}
+
+; CHECK: .section .text,"xr",discard,lnk2
+; CHECK: .globl lnk2
+define linkonce_odr dllexport void @lnk2() alwaysinline {
+	ret void
+}
+
+; CHECK: .section .text,"xr",discard,weak1
+; CHECK: .globl weak1
+define weak_odr dllexport void @weak1() {
+	ret void
+}
+
+
+; CHECK: .data
+; CHECK: .globl Var1
+@Var1 = dllexport global i32 1, align 4
+
+; CHECK: .rdata,"r"
+; CHECK: .globl Var2
+@Var2 = dllexport unnamed_addr constant i32 1
+
+; CHECK: .comm Var3
+@Var3 = common dllexport global i32 0, align 4
+
+; CHECK: .section .data,"w",discard,WeakVar1
+; CHECK: .globl WeakVar1
+@WeakVar1 = weak_odr dllexport global i32 1, align 4
+
+; CHECK: .section .rdata,"r",discard,WeakVar2
+; CHECK: .globl WeakVar2
+@WeakVar2 = weak_odr dllexport unnamed_addr constant i32 1
+
+
+; CHECK: .section .drectve
+; WIN32: /EXPORT:Var1,DATA
+; WIN32: /EXPORT:Var2,DATA
+; WIN32: /EXPORT:Var3,DATA
+; WIN32: /EXPORT:WeakVar1,DATA
+; WIN32: /EXPORT:WeakVar2,DATA
+; WIN32: /EXPORT:f1
+; WIN32: /EXPORT:f2
+; WIN32: /EXPORT:lnk1
+; WIN32: /EXPORT:lnk2
+; WIN32: /EXPORT:weak1
+; MINGW: -export:Var1,data
+; MINGW: -export:Var2,data
+; MINGW: -export:Var3,data
+; MINGW: -export:WeakVar1,data
+; MINGW: -export:WeakVar2,data
+; MINGW: -export:f1
+; MINGW: -export:f2
+; MINGW: -export:lnk1
+; MINGW: -export:lnk2
+; MINGW: -export:weak1
diff --git a/llvm/test/CodeGen/X86/dllexport.ll b/llvm/test/CodeGen/X86/dllexport.ll
index bf57e78f35d..1d992125976 100644
--- a/llvm/test/CodeGen/X86/dllexport.ll
+++ b/llvm/test/CodeGen/X86/dllexport.ll
@@ -1,12 +1,100 @@
-; RUN: llc < %s | FileCheck %s
-; PR2936
+; RUN: llc -mtriple i386-pc-win32 < %s | FileCheck -check-prefix=CHECK -check-prefix=WIN32 %s
+; RUN: llc -mtriple i386-pc-mingw32 < %s | FileCheck -check-prefix=CHECK -check-prefix=MINGW %s
 
-target triple = "i386-pc-mingw32"
+; CHECK: .text
 
-define dllexport x86_fastcallcc i32 @foo() nounwind  {
-entry:
+define void @notExported() {
+	ret void
+}
+
+; CHECK: .globl _f1
+define dllexport void @f1() {
+	ret void
+}
+
+; CHECK: .globl _f2
+define dllexport void @f2() unnamed_addr {
+	ret void
+}
+
+; CHECK: .globl _stdfun@0
+define dllexport x86_stdcallcc void @stdfun() nounwind {
+	ret void
+}
+
+; CHECK: .globl @fastfun@0
+define dllexport x86_fastcallcc i32 @fastfun() nounwind {
 	ret i32 0
 }
 
+; CHECK: .globl _thisfun
+define dllexport x86_thiscallcc void @thisfun() nounwind {
+	ret void
+}
+
+; CHECK: .section .text,"xr",discard,_lnk1
+; CHECK: .globl _lnk1
+define linkonce_odr dllexport void @lnk1() {
+	ret void
+}
+
+; CHECK: .section .text,"xr",discard,_lnk2
+; CHECK: .globl _lnk2
+define linkonce_odr dllexport void @lnk2() alwaysinline {
+	ret void
+}
+
+; CHECK: .section .text,"xr",discard,_weak1
+; CHECK: .globl _weak1
+define weak_odr dllexport void @weak1() {
+	ret void
+}
+
+
+; CHECK: .data
+; CHECK: .globl _Var1
+@Var1 = dllexport global i32 1, align 4
+
+; CHECK: .rdata,"r"
+; CHECK: .globl _Var2
+@Var2 = dllexport unnamed_addr constant i32 1
+
+; CHECK: .comm _Var3
+@Var3 = common dllexport global i32 0, align 4
+
+; CHECK: .section .data,"w",discard,_WeakVar1
+; CHECK: .globl _WeakVar1
+@WeakVar1 = weak_odr dllexport global i32 1, align 4
+
+; CHECK: .section .rdata,"r",discard,_WeakVar2
+; CHECK: .globl _WeakVar2
+@WeakVar2 = weak_odr dllexport unnamed_addr constant i32 1
+
+
 ; CHECK: .section .drectve
-; CHECK: -export:@foo@0
+; WIN32: /EXPORT:_Var1,DATA
+; WIN32: /EXPORT:_Var2,DATA
+; WIN32: /EXPORT:_Var3,DATA
+; WIN32: /EXPORT:_WeakVar1,DATA
+; WIN32: /EXPORT:_WeakVar2,DATA
+; WIN32: /EXPORT:_f1
+; WIN32: /EXPORT:_f2
+; WIN32: /EXPORT:_stdfun@0
+; WIN32: /EXPORT:@fastfun@0
+; WIN32: /EXPORT:_thisfun
+; WIN32: /EXPORT:_lnk1
+; WIN32: /EXPORT:_lnk2
+; WIN32: /EXPORT:_weak1
+; MINGW: -export:_Var1,data
+; MINGW: -export:_Var2,data
+; MINGW: -export:_Var3,data
+; MINGW: -export:_WeakVar1,data
+; MINGW: -export:_WeakVar2,data
+; MINGW: -export:_f1
+; MINGW: -export:_f2
+; MINGW: -export:_stdfun@0
+; MINGW: -export:@fastfun@0
+; MINGW: -export:_thisfun
+; MINGW: -export:_lnk1
+; MINGW: -export:_lnk2
+; MINGW: -export:_weak1
diff --git a/llvm/test/CodeGen/X86/dllimport-x86_64.ll b/llvm/test/CodeGen/X86/dllimport-x86_64.ll
new file mode 100644
index 00000000000..666409fd4c0
--- /dev/null
+++ b/llvm/test/CodeGen/X86/dllimport-x86_64.ll
@@ -0,0 +1,48 @@
+; RUN: llc -mtriple x86_64-pc-win32 < %s | FileCheck %s
+; RUN: llc -mtriple x86_64-pc-mingw32 < %s | FileCheck %s
+;
+; RUN: llc -mtriple x86_64-pc-mingw32 -O0 < %s | FileCheck %s -check-prefix=FAST
+; PR6275
+;
+; RUN: opt -mtriple x86_64-pc-win32 -std-compile-opts -S < %s | FileCheck %s -check-prefix=OPT
+
+@Var1 = external dllimport global i32
+@Var2 = available_externally dllimport unnamed_addr constant i32 1
+
+declare dllimport void @fun()
+
+define available_externally dllimport void @inline1() {
+	ret void
+}
+
+define available_externally dllimport void @inline2() {
+	ret void
+}
+
+declare void @dummy(...)
+
+define void @use() nounwind {
+; CHECK:     callq *__imp_fun(%rip)
+; FAST:      movq  __imp_fun(%rip), [[R:%[a-z]{3}]]
+; FAST-NEXT: callq *[[R]]
+  call void @fun()
+
+; CHECK: callq *__imp_inline1(%rip)
+; CHECK: callq *__imp_inline2(%rip)
+  call void @inline1()
+  call void @inline2()
+
+; available_externally uses go away
+; OPT-NOT: call void @inline1()
+; OPT-NOT: call void @inline2()
+; OPT-NOT: load i32* @Var2
+; OPT: call void (...)* @dummy(i32 %1, i32 1)
+
+; CHECK-DAG: movq __imp_Var1(%rip), [[R1:%[a-z]{3}]]
+; CHECK-DAG: movq __imp_Var2(%rip), [[R2:%[a-z]{3}]]
+  %1 = load i32* @Var1
+  %2 = load i32* @Var2
+  call void(...)* @dummy(i32 %1, i32 %2)
+
+  ret void
+}
diff --git a/llvm/test/CodeGen/X86/dllimport.ll b/llvm/test/CodeGen/X86/dllimport.ll
new file mode 100644
index 00000000000..695bfce821b
--- /dev/null
+++ b/llvm/test/CodeGen/X86/dllimport.ll
@@ -0,0 +1,59 @@
+; RUN: llc -mtriple i386-pc-win32 < %s | FileCheck %s
+; RUN: llc -mtriple i386-pc-mingw32 < %s | FileCheck %s
+;
+; RUN: llc -mtriple i386-pc-mingw32 -O0 < %s | FileCheck %s -check-prefix=FAST
+; PR6275
+;
+; RUN: opt -mtriple i386-pc-win32 -std-compile-opts -S < %s | FileCheck %s -check-prefix=OPT
+
+@Var1 = external dllimport global i32
+@Var2 = available_externally dllimport unnamed_addr constant i32 1
+
+declare dllimport void @fun()
+
+define available_externally dllimport void @inline1() {
+	ret void
+}
+
+define available_externally dllimport void @inline2() alwaysinline {
+	ret void
+}
+
+declare dllimport x86_stdcallcc void @stdfun() nounwind
+declare dllimport x86_fastcallcc void @fastfun() nounwind
+declare dllimport x86_thiscallcc void @thisfun() nounwind
+
+declare void @dummy(...)
+
+define void @use() nounwind {
+; CHECK:     calll *__imp__fun
+; FAST:      movl  __imp__fun, [[R:%[a-z]{3}]]
+; FAST-NEXT: calll *[[R]]
+  call void @fun()
+
+; CHECK: calll *__imp__inline1
+; CHECK: calll *__imp__inline2
+  call void @inline1()
+  call void @inline2()
+
+; CHECK: calll *__imp__stdfun@0
+; CHECK: calll *__imp_@fastfun@0
+; CHECK: calll *__imp__thisfun
+  call void @stdfun()
+  call void @fastfun()
+  call void @thisfun()
+
+; available_externally uses go away
+; OPT-NOT: call void @inline1()
+; OPT-NOT: call void @inline2()
+; OPT-NOT: load i32* @Var2
+; OPT: call void (...)* @dummy(i32 %1, i32 1)
+
+; CHECK-DAG: movl __imp__Var1, [[R1:%[a-z]{3}]]
+; CHECK-DAG: movl __imp__Var2, [[R2:%[a-z]{3}]]
+  %1 = load i32* @Var1
+  %2 = load i32* @Var2
+  call void(...)* @dummy(i32 %1, i32 %2)
+
+  ret void
+}