Merge pull request #16379 from JuliaLang/jb/exprcopy

only copy Exprs when copying IR

Author: vtjnash

base/expr.jl

@@ -23,14 +23,14 @@ end
 ## expressions ##
 
 copy(e::Expr) = (n = Expr(e.head);
-                 n.args = astcopy(e.args);
+                 n.args = copy_exprargs(e.args);
                  n.typ = e.typ;
                  n)
 
 # copy parts of an AST that the compiler mutates
-astcopy(x::Expr) = copy(x)
-astcopy(x::Array{Any,1}) = Any[astcopy(a) for a in x]
-astcopy(x) = x
+copy_exprs(x::Expr) = copy(x)
+copy_exprs(x::ANY) = x
+copy_exprargs(x::Array{Any,1}) = Any[copy_exprs(a) for a in x]
 
 ==(x::Expr, y::Expr) = x.head === y.head && isequal(x.args, y.args)
 ==(x::QuoteNode, y::QuoteNode) = isequal(x.value, y.value)

base/inference.jl

@@ -1397,7 +1397,7 @@ function unshare_linfo!(li::LambdaInfo)
     if !isa(li.code, Array{Any,1})
         li.code = ccall(:jl_uncompress_ast, Any, (Any,Any), li, li.code)
     else
-        li.code = astcopy(li.code)
+        li.code = copy_exprargs(li.code)
     end
     li.slotnames = copy(li.slotnames)
     li.slotflags = copy(li.slotflags)
@@ -2457,7 +2457,7 @@ function inlineable(f::ANY, ft::ANY, e::Expr, atypes::Vector{Any}, sv::Inference
     if !isa(ast,Array{Any,1})
         ast = ccall(:jl_uncompress_ast, Any, (Any,Any), linfo, ast)
     else
-        ast = astcopy(ast)
+        ast = copy_exprargs(ast)
     end
     ast = ast::Array{Any,1}