From 1327dfec807fa00782311f02d095b8e37ea55f2a Mon Sep 17 00:00:00 2001
From: Shuhei Kadowaki <40514306+aviatesk@users.noreply.github.com>
Date: Wed, 8 Nov 2023 09:51:16 +0900
Subject: [PATCH] allow destructive inlining only when the source is volatile
 (#52062)

Destructive inlining introduced by JuliaLang/julia#51934 implicitly
presupposes that inferred `CodeInfo` source has been compressed to the
`String` format when cached, which is not generally true for external
`AbstractInterpreter`s that may disable the `may_compress` and/or
`may_discard_trees` settings. This commit adds a safeguard to ensure the
eligibility of such `CodeInfo` source propagated by
`VolatileInferenceResult` for destructive inlining.
---
 base/compiler/ssair/inlining.jl | 2 +-
 base/compiler/typeinfer.jl      | 2 ++
 base/compiler/types.jl          | 3 ++-
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/base/compiler/ssair/inlining.jl b/base/compiler/ssair/inlining.jl
index db50c5142f46f..318b21b09bb16 100644
--- a/base/compiler/ssair/inlining.jl
+++ b/base/compiler/ssair/inlining.jl
@@ -884,7 +884,7 @@ function resolve_todo(mi::MethodInstance, result::Union{Nothing,InferenceResult,
     elseif isa(result, VolatileInferenceResult)
         inferred_result = get_local_result(result.inf_result)
         # volatile inference result can be inlined destructively
-        preserve_local_sources = OptimizationParams(state.interp).preserve_local_sources
+        preserve_local_sources = !result.inf_result.is_src_volatile | OptimizationParams(state.interp).preserve_local_sources
     else
         inferred_result = get_cached_result(state, mi)
     end
diff --git a/base/compiler/typeinfer.jl b/base/compiler/typeinfer.jl
index bf81c989c3155..9eef6615521ca 100644
--- a/base/compiler/typeinfer.jl
+++ b/base/compiler/typeinfer.jl
@@ -361,7 +361,9 @@ function transform_result_for_cache(interp::AbstractInterpreter,
     linfo::MethodInstance, valid_worlds::WorldRange, result::InferenceResult)
     inferred_result = result.src
     if inferred_result isa CodeInfo
+        uncompressed = inferred_result
         inferred_result = maybe_compress_codeinfo(interp, linfo, inferred_result)
+        result.is_src_volatile |= uncompressed !== inferred_result
     end
     # The global cache can only handle objects that codegen understands
     if !isa(inferred_result, MaybeCompressed)
diff --git a/base/compiler/types.jl b/base/compiler/types.jl
index 5c7445aec0386..db1d85cdddc40 100644
--- a/base/compiler/types.jl
+++ b/base/compiler/types.jl
@@ -76,12 +76,13 @@ mutable struct InferenceResult
     ipo_effects::Effects     # if inference is finished
     effects::Effects         # if optimization is finished
     argescapes               # ::ArgEscapeCache if optimized, nothing otherwise
+    is_src_volatile::Bool    # `src` has been cached globally as the compressed format already, allowing `src` to be used destructively
     function InferenceResult(linfo::MethodInstance, cache_argtypes::Vector{Any}, overridden_by_const::BitVector)
         # def = linfo.def
         # nargs = def isa Method ? Int(def.nargs) : 0
         # @assert length(cache_argtypes) == nargs
         return new(linfo, cache_argtypes, overridden_by_const, nothing, nothing,
-            WorldRange(), Effects(), Effects(), nothing)
+            WorldRange(), Effects(), Effects(), nothing, false)
     end
 end
 InferenceResult(linfo::MethodInstance, 𝕃::AbstractLattice=fallback_lattice) =