EA: remove no longer used is_ipo_profitable (#51391)

Author: aviatesk

base/compiler/ssair/EscapeAnalysis/EscapeAnalysis.jl

@@ -583,29 +583,6 @@ function ArgEscapeCache(estate::EscapeState)
     return ArgEscapeCache(argescapes, argaliases)
 end
 
-"""
-    is_ipo_profitable(ir::IRCode, nargs::Int) -> Bool
-
-Heuristically checks if there is any profitability to run the escape analysis on `ir`
-and generate IPO escape information cache. Specifically, this function examines
-if any call argument is "interesting" in terms of their escapability.
-"""
-function is_ipo_profitable(ir::IRCode, nargs::Int)
-    for i = 1:nargs
-        t = unwrap_unionall(widenconst(ir.argtypes[i]))
-        t <: IO && return false # bail out IO-related functions
-        is_ipo_profitable_type(t) && return true
-    end
-    return false
-end
-function is_ipo_profitable_type(@nospecialize t)
-    if isa(t, Union)
-        return is_ipo_profitable_type(t.a) && is_ipo_profitable_type(t.b)
-    end
-    (t === String || t === Symbol || t === Module || t === SimpleVector) && return false
-    return ismutabletype(t)
-end
-
 abstract type Change end
 struct EscapeChange <: Change
     xidx::Int

doc/src/devdocs/EscapeAnalysis.md

@@ -365,14 +365,10 @@ non-inlined callees that has been derived by previous `IPO EA`.
 More interestingly, it is also valid to use `IPO EA` escape information for type inference,
 e.g., inference accuracy can be improved by forming `Const`/`PartialStruct`/`MustAlias` of mutable object.
 
-Since the computational cost of `analyze_escapes` is not that cheap,
-both `IPO EA` and `Local EA` are better to run only when there is any profitability.
-Currently `EscapeAnalysis` provides the `is_ipo_profitable` heuristic to check a profitability of `IPO EA`.
 ```@docs
 Core.Compiler.EscapeAnalysis.analyze_escapes
 Core.Compiler.EscapeAnalysis.EscapeState
 Core.Compiler.EscapeAnalysis.EscapeInfo
-Core.Compiler.EscapeAnalysis.is_ipo_profitable
 ```
 
 --------------------------------------------------------------------------------------------

test/compiler/EscapeAnalysis/EAUtils.jl

@@ -65,7 +65,7 @@ using .CC:
     InferenceResult, OptimizationState, IRCode, copy as cccopy,
     @timeit, convert_to_ircode, slot2reg, compact!, ssa_inlining_pass!, sroa_pass!,
     adce_pass!, JLOptions, verify_ir, verify_linetable
-using .EA: analyze_escapes, ArgEscapeCache, EscapeInfo, EscapeState, is_ipo_profitable
+using .EA: analyze_escapes, ArgEscapeCache, EscapeInfo, EscapeState
 
 struct CodeCache
     cache::IdDict{MethodInstance,CodeInstance}