[X86] Add __builtin_ia32_selectss_128 and __builtin_ia32_selectsd_128 that is suitable for use in scalar mask intrinsics.

This will convert the i8 mask argument to <8 x i1> and extract an i1 and then emit a select instruction. This replaces the '(__U & 1)" and ternary operator used in some of intrinsics. The old sequence was lowered to a scalar and and compare. The new sequence uses an i1 vector that will interoperate better with other mask intrinsics.

This removes the need to handle div_ss/sd specially in CGBuiltin.cpp. A follow up patch will add the GCCBuiltin name back in llvm and remove the custom handling.

I made some adjustments to legacy move_ss/sd intrinsics which we reused here to do a simpler extract and insert instead of 2 extracts and two inserts or a shuffle.

llvm-svn: 336622

1 files changed, 7 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 6b1198d64e4..ba0519b3550 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -9832,6 +9832,13 @@ Value *CodeGenFunction::EmitX86BuiltinExpr(unsigned BuiltinID,
   case X86::BI__builtin_ia32_selectpd_256:
   case X86::BI__builtin_ia32_selectpd_512:
     return EmitX86Select(*this, Ops[0], Ops[1], Ops[2]);
+  case X86::BI__builtin_ia32_selectss_128:
+  case X86::BI__builtin_ia32_selectsd_128: {
+    Value *A = Builder.CreateExtractElement(Ops[1], (uint64_t)0);
+    Value *B = Builder.CreateExtractElement(Ops[2], (uint64_t)0);
+    A = EmitX86ScalarSelect(*this, Ops[0], A, B);
+    return Builder.CreateInsertElement(Ops[1], A, (uint64_t)0);
+  }
   case X86::BI__builtin_ia32_cmpb128_mask:
   case X86::BI__builtin_ia32_cmpb256_mask:
   case X86::BI__builtin_ia32_cmpb512_mask: