inference: follow up JuliaLang#49260, remove no longer necessary func…

…tions (JuliaLang#55430)

base/compiler/inferencestate.jl

@@ -517,72 +517,6 @@ function compute_trycatch(code::Vector{Any}, bbs::Union{Vector{BasicBlock},Nothi
  return handler_info
 end
 
-function is_throw_call(e::Expr, code::Vector{Any})
- if e.head === :call
- f = e.args[1]
- if isa(f, SSAValue)
- f = code[f.id]
- end
- if isa(f, GlobalRef)
- ff = abstract_eval_globalref_type(f)
- if isa(ff, Const) && ff.val === Core.throw
- return true
- end
- end
- end
- return false
-end
-
-function mark_throw_blocks!(src::CodeInfo, handler_info::Union{Nothing,HandlerInfo})
- for stmt in find_throw_blocks(src.code, handler_info)
- src.ssaflags[stmt] |= IR_FLAG_THROW_BLOCK
- end
- return nothing
-end
-
-# this utility function is incomplete and won't catch every block that always throws, since:
-# - it only recognizes direct calls to `throw` within the target code, so it can't mark
-# blocks that deterministically call `throw` internally, like those containing `error`.
-# - it just does a reverse linear traverse of statements, there's a chance it might miss
-# blocks, particularly when there are reverse control edges.
-function find_throw_blocks(code::Vector{Any}, handler_info::Union{Nothing,HandlerInfo})
- stmts = BitSet()
- n = length(code)
- for i in n:-1:1
- s = code[i]
- if isa(s, Expr)
- if s.head === :gotoifnot
- if i+1 in stmts && s.args[2]::Int in stmts
- push!(stmts, i)
- end
- elseif s.head === :return
- # see `ReturnNode` handling
- elseif is_throw_call(s, code)
- if handler_info === nothing || handler_info.handler_at[i][1] == 0
- push!(stmts, i)
- end
- elseif i+1 in stmts
- push!(stmts, i)
- end
- elseif isa(s, ReturnNode)
- # NOTE: it potentially makes sense to treat unreachable nodes
- # (where !isdefined(s, :val)) as `throw` points, but that can cause
- # worse codegen around the call site (issue #37558)
- elseif isa(s, GotoNode)
- if s.label in stmts
- push!(stmts, i)
- end
- elseif isa(s, GotoIfNot)
- if i+1 in stmts && s.dest in stmts
- push!(stmts, i)
- end
- elseif i+1 in stmts
- push!(stmts, i)
- end
- end
- return stmts
-end
-
 # check if coverage mode is enabled
 function should_insert_coverage(mod::Module, debuginfo::DebugInfo)
  coverage_enabled(mod) && return true