r220859 - CodeGen: add __readfsdword builtin

[Saleem Abdulrasool]

Author: compnerd
Date: Wed Oct 29 11:35:41 2014
New Revision: 220859

URL: http://llvm.org/viewvc/llvm-project?rev=220859&view=rev
Log:
CodeGen: add __readfsdword builtin

The Windows NT SDK uses __readfsdword and declares it as a compiler provided
builtin (#pragma intrinsic(__readfsword).  Because intrin.h is not referenced
by winnt.h, it is not possible to provide an out-of-line definition for the
intrinsic.  Provide a proper compiler builtin definition.

Modified:
    cfe/trunk/include/clang/Basic/Builtins.def
    cfe/trunk/lib/CodeGen/CGBuiltin.cpp
    cfe/trunk/lib/Headers/Intrin.h
    cfe/trunk/test/CodeGen/ms-intrinsics.c

Modified: cfe/trunk/include/clang/Basic/Builtins.def
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/Builtins.def?rev=220859&r1=220858&r2=220859&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/Builtins.def (original)
+++ cfe/trunk/include/clang/Basic/Builtins.def Wed Oct 29 11:35:41 2014
@@ -703,6 +703,7 @@ LANGBUILTIN(_InterlockedDecrement, "LiLi
 LANGBUILTIN(_InterlockedExchangeAdd, "LiLiD*Li", "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(_InterlockedExchangePointer, "v*v*D*v*", "n", ALL_MS_LANGUAGES)
 LANGBUILTIN(_InterlockedExchange, "LiLiD*Li", "n", ALL_MS_LANGUAGES)
+LANGBUILTIN(__readfsdword, "ULiULi", "n", ALL_MS_LANGUAGES)
 
 // C99 library functions
 // C99 stdlib.h

Modified: cfe/trunk/lib/CodeGen/CGBuiltin.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGBuiltin.cpp?rev=220859&r1=220858&r2=220859&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGBuiltin.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGBuiltin.cpp Wed Oct 29 11:35:41 2014
@@ -1624,6 +1624,14 @@ RValue CodeGenFunction::EmitBuiltinExpr(
     RMWI->setVolatile(true);
     return RValue::get(RMWI);
   }
+  case Builtin::BI__readfsdword: {
+    Value *IntToPtr =
+      Builder.CreateIntToPtr(EmitScalarExpr(E->getArg(0)),
+                             llvm::PointerType::get(CGM.Int32Ty, 257));
+    LoadInst *Load =
+        Builder.CreateAlignedLoad(IntToPtr, /*Align=*/4, /*isVolatile=*/true);
+    return RValue::get(Load);
+  }
   }
 
   // If this is an alias for a lib function (e.g. __builtin_sin), emit

Modified: cfe/trunk/lib/Headers/Intrin.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Headers/Intrin.h?rev=220859&r1=220858&r2=220859&view=diff
==============================================================================
--- cfe/trunk/lib/Headers/Intrin.h (original)
+++ cfe/trunk/lib/Headers/Intrin.h Wed Oct 29 11:35:41 2014
@@ -861,10 +861,6 @@ static __inline__ unsigned char __attrib
 __readfsbyte(unsigned long __offset) {
   return *__ptr_to_addr_space(257, unsigned char, __offset);
 }
-static __inline__ unsigned long __attribute__((__always_inline__, __nodebug__))
-__readfsdword(unsigned long __offset) {
-  return *__ptr_to_addr_space(257, unsigned long, __offset);
-}
 static __inline__ unsigned __int64 __attribute__((__always_inline__, __nodebug__))
 __readfsqword(unsigned long __offset) {
   return *__ptr_to_addr_space(257, unsigned __int64, __offset);

Modified: cfe/trunk/test/CodeGen/ms-intrinsics.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ms-intrinsics.c?rev=220859&r1=220858&r2=220859&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/ms-intrinsics.c (original)
+++ cfe/trunk/test/CodeGen/ms-intrinsics.c Wed Oct 29 11:35:41 2014
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -triple i686--windows -fms-compatibility -Oz -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple i686--windows -fms-compatibility -Oz -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK -check-prefix CHECK-I386
 // RUN: %clang_cc1 -triple thumbv7--windows -fms-compatibility -Oz -emit-llvm %s -o - | FileCheck %s
 
 void *test_InterlockedExchangePointer(void * volatile *Target, void *Value) {
@@ -36,3 +36,16 @@ long test_InterlockedExchange(long *Targ
 // CHECK:   %[[EXCHANGE:[0-9]+]] = atomicrmw xchg i32* %Target, i32 %Value seq_cst
 // CHECK:   ret i32 %[[EXCHANGE:[0-9]+]]
 // CHECK: }
+
+#if defined(__i386__)
+long test__readfsdword(unsigned long Offset) {
+  return __readfsdword(Offset);
+}
+
+// CHECK-I386: define i32 @test__readfsdword(i32 %Offset){{.*}}{
+// CHECK-I386:   %0 = inttoptr i32 %Offset to i32 addrspace(257)*
+// CHECK-I386:   %1 = load volatile i32 addrspace(257)* %0, align 4
+// CHECK-I386:   ret i32 %1
+// CHECK-I386: }
+#endif
+