r295107 - MS inline asm: Filter MXCSR out of the inferred clobber list

[Reid Kleckner via cfe-commits]

Author: rnk
Date: Tue Feb 14 15:38:17 2017
New Revision: 295107

URL: http://llvm.org/viewvc/llvm-project?rev=295107&view=rev
Log:
MS inline asm: Filter MXCSR out of the inferred clobber list

Since r295004, LLVM has started modelling this new register, but we
don't have GCC constraint inline asm spellings for it yet.

Modified:
    cfe/trunk/lib/Parse/ParseStmtAsm.cpp
    cfe/trunk/test/CodeGen/ms-inline-asm.c

Modified: cfe/trunk/lib/Parse/ParseStmtAsm.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParseStmtAsm.cpp?rev=295107&r1=295106&r2=295107&view=diff
==============================================================================
--- cfe/trunk/lib/Parse/ParseStmtAsm.cpp (original)
+++ cfe/trunk/lib/Parse/ParseStmtAsm.cpp Tue Feb 14 15:38:17 2017
@@ -621,10 +621,11 @@ StmtResult Parser::ParseMicrosoftAsmStat
                                MII.get(), IP.get(), Callback))
     return StmtError();
 
-  // Filter out "fpsw".  Clang doesn't accept it, and it always lists flags and
-  // fpsr as clobbers.
-  auto End = std::remove(Clobbers.begin(), Clobbers.end(), "fpsw");
-  Clobbers.erase(End, Clobbers.end());
+  // Filter out "fpsw" and "mxcsr". They aren't valid GCC asm clobber
+  // constraints. Clang always adds fpsr to the clobber list anyway.
+  llvm::erase_if(Clobbers, [](const std::string &C) {
+    return C == "fpsw" || C == "mxcsr";
+  });
 
   // Build the vector of clobber StringRefs.
   ClobberRefs.insert(ClobberRefs.end(), Clobbers.begin(), Clobbers.end());

Modified: cfe/trunk/test/CodeGen/ms-inline-asm.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ms-inline-asm.c?rev=295107&r1=295106&r2=295107&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/ms-inline-asm.c (original)
+++ cfe/trunk/test/CodeGen/ms-inline-asm.c Tue Feb 14 15:38:17 2017
@@ -649,6 +649,14 @@ void label6(){
   // CHECK: call void asm sideeffect inteldialect "jmp {{.*}}__MSASMLABEL_.${:uid}__label\0A\09{{.*}}__MSASMLABEL_.${:uid}__label:", "~{dirflag},~{fpsr},~{flags}"()
 }
 
+// Don't include mxcsr in the clobber list.
+void mxcsr() {
+  char buf[4096];
+  __asm fxrstor buf
+}
+// CHECK-LABEL: define void @mxcsr
+// CHECK: call void asm sideeffect inteldialect "fxrstor byte ptr $0", "=*m,~{dirflag},~{fpsr},~{flags}"
+
 typedef union _LARGE_INTEGER {
   struct {
     unsigned int LowPart;