Implements the @nonans decorator to enable some LLVM vectorizations

base/compiler/ssair/legacy.jl

@@ -57,6 +57,12 @@ function replace_code_newstyle!(ci::CodeInfo, ir::IRCode, nargs::Int)
  ci.linetable = ir.linetable
  ci.ssavaluetypes = ir.types
  ci.ssaflags = ir.flags
+ for metanode in ir.meta
+ push!(ci.code, metanode)
+ push!(ci.codelocs, 1)
+ push!(ci.ssavaluetypes, Any)
+ push!(ci.ssaflags, 0x00)
+ end
  # Translate BB Edges to statement edges
  # (and undo normalization for now)
  for i = 1:length(ci.code)

base/exports.jl

@@ -971,6 +971,7 @@ export
  @nospecialize,
  @specialize,
  @polly,
+ @nonans,
 
  @assert,
  @__dot__,

base/expr.jl

@@ -256,6 +256,23 @@ macro polly(ex)
  esc(isa(ex, Expr) ? pushmeta!(ex, :polly) : ex)
 end
 
+"""
+ @nonans
+
+Allows the compiler to assume no NaNs on floating-point operations.
+
+```julia
+@nonans function mathfunc(x)
+ #=
+ Function Definition
+ =#
+end
+```
+"""
+macro nonans(ex)
+ esc(isa(ex, Expr) ? pushmeta!(ex, :nonans) : ex)
+end
+
 ## some macro utilities ##
 
 function pushmeta!(ex::Expr, sym::Symbol, args::Any...)

src/ast.c

@@ -62,6 +62,7 @@ jl_sym_t *throw_undef_if_not_sym; jl_sym_t *getfield_undefref_sym;
 jl_sym_t *gc_preserve_begin_sym; jl_sym_t *gc_preserve_end_sym;
 jl_sym_t *escape_sym;
 jl_sym_t *aliasscope_sym; jl_sym_t *popaliasscope_sym;
+jl_sym_t *nonans_sym;
 
 static uint8_t flisp_system_image[] = {
 #include <julia_flisp.boot.inc>
@@ -367,6 +368,7 @@ void jl_init_frontend(void)
  do_sym = jl_symbol("do");
  aliasscope_sym = jl_symbol("aliasscope");
  popaliasscope_sym = jl_symbol("popaliasscope");
+ nonans_sym = jl_symbol("nonans");
 }
 
 JL_DLLEXPORT void jl_lisp_prompt(void)

src/codegen.cpp

@@ -5618,6 +5618,10 @@ static std::unique_ptr<Module> emit_function(
  f->addFnAttr(Attribute::NoInline);
  }
 
+ if (jl_has_meta(stmts, nonans_sym)) {
+ f->addFnAttr("no-nans-fp-math", "true");
+ }
+
  if (returninfo.cc == jl_returninfo_t::Union) {
  f->addAttribute(1, Attribute::getWithDereferenceableBytes(jl_LLVMContext, returninfo.union_bytes));
  f->addAttribute(1, Attribute::getWithAlignment(jl_LLVMContext, returninfo.union_align));

src/julia_internal.h

@@ -1053,6 +1053,7 @@ extern jl_sym_t *throw_undef_if_not_sym; extern jl_sym_t *getfield_undefref_sym;
 extern jl_sym_t *gc_preserve_begin_sym; extern jl_sym_t *gc_preserve_end_sym;
 extern jl_sym_t *failed_sym; extern jl_sym_t *done_sym; extern jl_sym_t *runnable_sym;
 extern jl_sym_t *escape_sym;
+extern jl_sym_t *nonans_sym;
 
 struct _jl_sysimg_fptrs_t;