Mark math lib intrinsics readonly, on the grounds

that they read the rounding mode.  This is conservatively
correct, which they weren't before.  We can do more
optimization on these if we actually model the rounding
mode.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55860 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 1 deletions

diff --git a/include/llvm/Intrinsics.td b/include/llvm/Intrinsics.td
index dc428460ff..5dd1d6116d 100644
--- a/include/llvm/Intrinsics.td
+++ b/include/llvm/Intrinsics.td
@@ -193,7 +193,10 @@ let Properties = [IntrWriteArgMem] in {
                                    llvm_i64_ty, llvm_i32_ty]>;
 }
 
-let Properties = [IntrNoMem] in {
+// These functions do not actually read memory, but they are sensitive to the
+// rounding mode.  This needs to be modelled separately; in the meantime
+// declaring them as reading memory is conservatively correct.
+let Properties = [IntrReadMem] in {
   def int_sqrt : Intrinsic<[llvm_anyfloat_ty, LLVMMatchType<0>]>;
   def int_powi : Intrinsic<[llvm_anyfloat_ty, LLVMMatchType<0>, llvm_i32_ty]>;
   def int_sin  : Intrinsic<[llvm_anyfloat_ty, LLVMMatchType<0>]>;