Rollup merge of #128970 - DianQK:lint-llvm-ir, r=nikic

Add `-Zlint-llvm-ir`

This flag is similar to `-Zverify-llvm-ir` and allows us to lint the generated IR.

r? compiler

6 files changed, 15 insertions, 1 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index adf7e933f43..a5c27d2282e 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -571,6 +571,7 @@ pub(crate) unsafe fn llvm_optimize(
             cgcx.opts.cg.linker_plugin_lto.enabled(),
             config.no_prepopulate_passes,
             config.verify_llvm_ir,
+            config.lint_llvm_ir,
             using_thin_buffers,
             config.merge_functions,
             unroll_loops,
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 5e0d7418993..138cc3219aa 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -2225,6 +2225,7 @@ unsafe extern "C" {
         IsLinkerPluginLTO: bool,
         NoPrepopulatePasses: bool,
         VerifyIR: bool,
+        LintIR: bool,
         UseThinLTOBuffers: bool,
         MergeFunctions: bool,
         UnrollLoops: bool,
diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 7ad31802454..feb27c148a1 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -112,6 +112,7 @@ pub struct ModuleConfig {
     // Miscellaneous flags. These are mostly copied from command-line
     // options.
     pub verify_llvm_ir: bool,
+    pub lint_llvm_ir: bool,
     pub no_prepopulate_passes: bool,
     pub no_builtins: bool,
     pub time_module: bool,
@@ -237,6 +238,7 @@ impl ModuleConfig {
             bc_cmdline: sess.target.bitcode_llvm_cmdline.to_string(),
 
             verify_llvm_ir: sess.verify_llvm_ir(),
+            lint_llvm_ir: sess.opts.unstable_opts.lint_llvm_ir,
             no_prepopulate_passes: sess.opts.cg.no_prepopulate_passes,
             no_builtins: no_builtins || sess.target.no_builtins,
 
diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs
index 3de445fb2cb..844d8ef02e0 100644
--- a/compiler/rustc_interface/src/tests.rs
+++ b/compiler/rustc_interface/src/tests.rs
@@ -795,6 +795,7 @@ fn test_unstable_options_tracking_hash() {
     tracked!(instrument_xray, Some(InstrumentXRay::default()));
     tracked!(link_directives, false);
     tracked!(link_only, true);
+    tracked!(lint_llvm_ir, true);
     tracked!(llvm_module_flag, vec![("bar".to_string(), 123, "max".to_string())]);
     tracked!(llvm_plugins, vec![String::from("plugin_name")]);
     tracked!(location_detail, LocationDetail { file: true, line: false, column: false });
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 9884ed15b8a..c7306b0516f 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -713,7 +713,7 @@ extern "C" LLVMRustResult LLVMRustOptimize(
     LLVMModuleRef ModuleRef, LLVMTargetMachineRef TMRef,
     LLVMRustPassBuilderOptLevel OptLevelRust, LLVMRustOptStage OptStage,
     bool IsLinkerPluginLTO, bool NoPrepopulatePasses, bool VerifyIR,
-    bool UseThinLTOBuffers, bool MergeFunctions, bool UnrollLoops,
+    bool LintIR, bool UseThinLTOBuffers, bool MergeFunctions, bool UnrollLoops,
     bool SLPVectorize, bool LoopVectorize, bool DisableSimplifyLibCalls,
     bool EmitLifetimeMarkers, LLVMRustSanitizerOptions *SanitizerOptions,
     const char *PGOGenPath, const char *PGOUsePath, bool InstrumentCoverage,
@@ -842,6 +842,13 @@ extern "C" LLVMRustResult LLVMRustOptimize(
         });
   }
 
+  if (LintIR) {
+    PipelineStartEPCallbacks.push_back(
+        [](ModulePassManager &MPM, OptimizationLevel Level) {
+          MPM.addPass(createModuleToFunctionPassAdaptor(LintPass()));
+        });
+  }
+
   if (InstrumentGCOV) {
     PipelineStartEPCallbacks.push_back(
         [](ModulePassManager &MPM, OptimizationLevel Level) {
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index ab1e4488a9f..4492ad09357 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -1811,6 +1811,8 @@ options! {
         "link the `.rlink` file generated by `-Z no-link` (default: no)"),
     linker_features: LinkerFeaturesCli = (LinkerFeaturesCli::default(), parse_linker_features, [UNTRACKED],
         "a comma-separated list of linker features to enable (+) or disable (-): `lld`"),
+    lint_llvm_ir: bool = (false, parse_bool, [TRACKED],
+        "lint LLVM IR (default: no)"),
     lint_mir: bool = (false, parse_bool, [UNTRACKED],
         "lint MIR before and after each transformation"),
     llvm_module_flag: Vec<(String, u32, String)> = (Vec::new(), parse_llvm_module_flag, [TRACKED],