[NVPTX] Infer __nvvm_reflect as nounwind, readnone
This patch simply mirrors the attributes we give to @llvm.nvvm.reflect
to the __nvvm_reflect libdevice call. This shaves about 30% of the code
in libdevice away because of CSE opportunities. It's also helps us
figure out that libdevice implementations of transcendental functions
don't have side-effects.
llvm-svn: 265060
diff --git a/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp b/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp
index 16922ab..030a646 100644
--- a/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/InferFunctionAttrs.cpp
@@ -924,6 +924,15 @@
Changed |= setOnlyReadsMemory(F, 2);
return Changed;
+ // int __nvvm_reflect(const char *)
+ case LibFunc::nvvm_reflect:
+ if (FTy->getNumParams() != 1 || !isa<PointerType>(FTy->getParamType(0)))
+ return false;
+
+ Changed |= setDoesNotAccessMemory(F);
+ Changed |= setDoesNotThrow(F);
+ return Changed;
+
default:
// FIXME: It'd be really nice to cover all the library functions we're
// aware of here.