From 5026492e07f358036a1703107d082158b955b368 Mon Sep 17 00:00:00 2001
From: Simonas Kazlauskas <git@kazlauskas.me>
Date: Wed, 24 Nov 2021 21:13:53 +0200
Subject: [PATCH] [1.57] Disable LLVM newPM by default
---
compiler/rustc_codegen_llvm/src/back/write.rs | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 380dfd387235d..b6d682f23238c 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -378,18 +378,14 @@ fn get_pgo_sample_use_path(config: &ModuleConfig) -> Option<CString> {
}
pub(crate) fn should_use_new_llvm_pass_manager(
- cgcx: &CodegenContext<LlvmCodegenBackend>,
+ _cgcx: &CodegenContext<LlvmCodegenBackend>,
config: &ModuleConfig,
) -> bool {
- // The new pass manager is enabled by default for LLVM >= 13.
- // This matches Clang, which also enables it since Clang 13.
-
- // FIXME: There are some perf issues with the new pass manager
- // when targeting s390x, so it is temporarily disabled for that
- // arch, see https://github.com/rust-lang/rust/issues/89609
+ // The new pass manager is causing significant performance issues such as #91128, and is
+ // therefore disabled in stable versions of rustc by default.
config
.new_llvm_pass_manager
- .unwrap_or_else(|| cgcx.target_arch != "s390x" && llvm_util::get_version() >= (13, 0, 0))
+ .unwrap_or(false)
}
pub(crate) unsafe fn optimize_with_new_llvm_pass_manager(