[X86] Implement __builtin_cpu_is

This patch adds support for __builtin_cpu_is. I've tried to match the strings supported to the latest version of gcc.

Differential Revision: https://reviews.llvm.org/D35449

llvm-svn: 310657

1 files changed, 23 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 0112bffa29b..e75c15a37cd 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -1841,6 +1841,26 @@ static bool SemaBuiltinCpuSupports(Sema &S, CallExpr *TheCall) {
   return false;
 }
 
+/// SemaBuiltinCpuIs - Handle __builtin_cpu_is(char *).
+/// This checks that the target supports __builtin_cpu_is and
+/// that the string argument is constant and valid.
+static bool SemaBuiltinCpuIs(Sema &S, CallExpr *TheCall) {
+  Expr *Arg = TheCall->getArg(0);
+
+  // Check if the argument is a string literal.
+  if (!isa<StringLiteral>(Arg->IgnoreParenImpCasts()))
+    return S.Diag(TheCall->getLocStart(), diag::err_expr_not_string_literal)
+           << Arg->getSourceRange();
+
+  // Check the contents of the string.
+  StringRef Feature =
+      cast<StringLiteral>(Arg->IgnoreParenImpCasts())->getString();
+  if (!S.Context.getTargetInfo().validateCpuIs(Feature))
+    return S.Diag(TheCall->getLocStart(), diag::err_invalid_cpu_is)
+           << Arg->getSourceRange();
+  return false;
+}
+
 // Check if the rounding mode is legal.
 bool Sema::CheckX86BuiltinRoundingOrSAE(unsigned BuiltinID, CallExpr *TheCall) {
   // Indicates if this instruction has rounding control or just SAE.
@@ -2154,6 +2174,9 @@ bool Sema::CheckX86BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
   if (BuiltinID == X86::BI__builtin_cpu_supports)
     return SemaBuiltinCpuSupports(*this, TheCall);
 
+  if (BuiltinID == X86::BI__builtin_cpu_is)
+    return SemaBuiltinCpuIs(*this, TheCall);
+
   // If the intrinsic has rounding or SAE make sure its valid.
   if (CheckX86BuiltinRoundingOrSAE(BuiltinID, TheCall))
     return true;