Merge pull request #42805 from JuliaLang/avi/backport-42766

backport #42766 into `backports-release-1.7`
JuliaLang · Oct 27, 2021 · f662b0a · f662b0a
2 parents 069861a + c22889e
commit f662b0a
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Showing 3 changed files with 319 additions and 149 deletions.
diff --git a/base/compiler/abstractinterpretation.jl b/base/compiler/abstractinterpretation.jl
@@ -568,17 +568,27 @@ end
 function maybe_get_const_prop_profitable(interp::AbstractInterpreter, result::MethodCallResult,
                                          @nospecialize(f), argtypes::Vector{Any}, match::MethodMatch,
                                          sv::InferenceState)
-    const_prop_entry_heuristic(interp, result, sv) || return nothing
+    if !InferenceParams(interp).ipo_constant_propagation
+        add_remark!(interp, sv, "[constprop] Disabled by parameter")
+        return nothing
+    end
     method = match.method
+    force = force_const_prop(interp, f, method)
+    force || const_prop_entry_heuristic(interp, result, sv) || return nothing
     nargs::Int = method.nargs
     method.isva && (nargs -= 1)
-    if length(argtypes) < nargs
+    length(argtypes) < nargs && return nothing
+    if !(const_prop_argument_heuristic(interp, argtypes) || const_prop_rettype_heuristic(interp, result.rt))
+        add_remark!(interp, sv, "[constprop] Disabled by argument and rettype heuristics")
         return nothing
     end
-    const_prop_argument_heuristic(interp, argtypes) || const_prop_rettype_heuristic(interp, result.rt) || return nothing
     allconst = is_allconst(argtypes)
-    force = force_const_prop(interp, f, method)
-    force || const_prop_function_heuristic(interp, f, argtypes, nargs, allconst) || return nothing
+    if !force
+        if !const_prop_function_heuristic(interp, f, argtypes, nargs, allconst)
+            add_remark!(interp, sv, "[constprop] Disabled by function heuristic")
+            return nothing
+        end
+    end
     force |= allconst
     mi = specialize_method(match, !force)
     if mi === nothing
@@ -594,8 +604,13 @@ function maybe_get_const_prop_profitable(interp::AbstractInterpreter, result::Me
 end
 
 function const_prop_entry_heuristic(interp::AbstractInterpreter, result::MethodCallResult, sv::InferenceState)
-    call_result_unused(sv) && result.edgecycle && return false
-    return is_improvable(result.rt) && InferenceParams(interp).ipo_constant_propagation
+    if call_result_unused(sv) && result.edgecycle
+        add_remark!(interp, sv, "[constprop] Disabled by entry heuristic (edgecycle with unused result)")
+        return false
+    end
+    is_improvable(result.rt) && return true
+    add_remark!(interp, sv, "[constprop] Disabled by entry heuristic (unimprovable return type)")
+    return false
 end
 
 # see if propagating constants may be worthwhile