From 3be167f606ddfed976be58c5fd8756c91f61ab16 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 1 Oct 2010 23:23:24 +0000
Subject: [PATCH] diagnose errors when a builtin that require constant
 arguments don't have them. For example, on:

#include <emmintrin.h>
int foo(int N) {
 __m128i white2;
 white2 = _mm_slli_si128(white2, N);
 return 0;
}

we used to get:
fatal error: error in backend: Cannot yet select: intrinsic %llvm.x86.sse2.psll.dq

now we get:
/Users/sabre/t.c:4:11: error: argument to '__builtin_ia32_pslldqi128' must be a
      constant integer
 white2 = _mm_slli_si128(white2, N);
          ^~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /Users/sabre/t.c:1:
/Volumes/Projects/cvs/llvm/Debug+Asserts/lib/clang/2.9/include/emmintrin.h:781:13: note: instantiated from:
  ((__m128i)__builtin_ia32_pslldqi128((__m128i)(VEC), (IMM)*8))
            ^                                         ~~~~~~~
1 error generated.

llvm-svn: 115374
---
 clang/lib/Sema/SemaChecking.cpp       | 18 ++++++++++++++++++
 clang/test/Sema/x86-builtin-palignr.c | 10 ++++++++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index c4e86875ed8e..4b1f423028d1 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -131,6 +131,24 @@ ExprResult
 Sema::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
   ExprResult TheCallResult(Owned(TheCall));
 
+  // Find out if any arguments are required to be integer constant expressions.
+  unsigned ICEArguments = 0;
+  ASTContext::GetBuiltinTypeError Error;
+  Context.GetBuiltinType(BuiltinID, Error, &ICEArguments);
+  if (Error != ASTContext::GE_None)
+    ICEArguments = 0;  // Don't diagnose previously diagnosed errors.
+  
+  // If any arguments are required to be ICE's, check and diagnose.
+  for (unsigned ArgNo = 0; ICEArguments != 0; ++ArgNo) {
+    // Skip arguments not required to be ICE's.
+    if ((ICEArguments & (1 << ArgNo)) == 0) continue;
+    
+    llvm::APSInt Result;
+    if (SemaBuiltinConstantArg(TheCall, ArgNo, Result))
+      return true;
+    ICEArguments &= ~(1 << ArgNo);
+  }
+  
   switch (BuiltinID) {
   case Builtin::BI__builtin___CFStringMakeConstantString:
     assert(TheCall->getNumArgs() == 1 &&
diff --git a/clang/test/Sema/x86-builtin-palignr.c b/clang/test/Sema/x86-builtin-palignr.c
index eedf99bdfb6f..8f90c81fd8a3 100644
--- a/clang/test/Sema/x86-builtin-palignr.c
+++ b/clang/test/Sema/x86-builtin-palignr.c
@@ -4,7 +4,13 @@
 
 #include <tmmintrin.h>
 
-__m64 foo(__m64 a, __m64 b, int c)
-{
+__m64 test1(__m64 a, __m64 b, int c) {
    return _mm_alignr_pi8(a, b, c); // expected-error {{argument to '__builtin_ia32_palignr' must be a constant integer}}
 }
+
+int test2(int N) {
+ __m128i white2;
+ white2 = __builtin_ia32_pslldqi128(white2, N); // expected-error {{argument to '__builtin_ia32_pslldqi128' must be a constant integer}}
+ return 0;
+} 
+