Auto merge of #51007 - AstralSorcerer:master, r=nagisa

Make globals with private linkage unnamed. Fixes #50862.

cc @oli-obk @nagisa

diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index a5c6a0d5cd690e4828b2b4595db3220b9a7cb291..5e23c6e868f47200e2a4d2131ae18dfee4bf357c 100644 (file)
--- a/src/librustc_codegen_llvm/back/write.rs
+++ b/src/librustc_codegen_llvm/back/write.rs
@@ -541,11 +541,23 @@ unsafe fn optimize(cgcx: &CodegenContext,
             };
 
             if config.verify_llvm_ir { assert!(addpass("verify")); }
+
+            // Some options cause LLVM bitcode to be emitted, which uses ThinLTOBuffers, so we need
+            // to make sure we run LLVM's NameAnonGlobals pass when emitting bitcode; otherwise
+            // we'll get errors in LLVM.
+            let using_thin_buffers = llvm::LLVMRustThinLTOAvailable() && (config.emit_bc
+                || config.obj_is_bitcode || config.emit_bc_compressed || config.embed_bitcode);
+            let mut have_name_anon_globals_pass = false;
             if !config.no_prepopulate_passes {
                 llvm::LLVMRustAddAnalysisPasses(tm, fpm, llmod);
                 llvm::LLVMRustAddAnalysisPasses(tm, mpm, llmod);
                 let opt_level = config.opt_level.unwrap_or(llvm::CodeGenOptLevel::None);
                 let prepare_for_thin_lto = cgcx.lto == Lto::Thin || cgcx.lto == Lto::ThinLocal;
+                have_name_anon_globals_pass = have_name_anon_globals_pass || prepare_for_thin_lto;
+                if using_thin_buffers && !prepare_for_thin_lto {
+                    assert!(addpass("name-anon-globals"));
+                    have_name_anon_globals_pass = true;
+                }
                 with_llvm_pmb(llmod, &config, opt_level, prepare_for_thin_lto, &mut |b| {
                     llvm::LLVMPassManagerBuilderPopulateFunctionPassManager(b, fpm);
                     llvm::LLVMPassManagerBuilderPopulateModulePassManager(b, mpm);
@@ -557,6 +569,9 @@ unsafe fn optimize(cgcx: &CodegenContext,
                     diag_handler.warn(&format!("unknown pass `{}`, ignoring",
                                             pass));
                 }
+                if pass == "name-anon-globals" {
+                    have_name_anon_globals_pass = true;
+                }
             }
 
             for pass in &cgcx.plugin_passes {
@@ -565,6 +580,22 @@ unsafe fn optimize(cgcx: &CodegenContext,
                                             `{}` but LLVM does not \
                                             recognize it", pass));
                 }
+                if pass == "name-anon-globals" {
+                    have_name_anon_globals_pass = true;
+                }
+            }
+
+            if using_thin_buffers && !have_name_anon_globals_pass {
+                // As described above, this will probably cause an error in LLVM
+                if config.no_prepopulate_passes {
+                    diag_handler.err("The current compilation is going to use thin LTO buffers \
+                                     without running LLVM's NameAnonGlobals pass. \
+                                     This will likely cause errors in LLVM. Consider adding \
+                                     -C passes=name-anon-globals to the compiler command line.");
+                } else {
+                    bug!("We are using thin LTO buffers without running the NameAnonGlobals pass. \
+                         This will likely cause errors in LLVM and shoud never happen.");
+                }
             }
         }
 

diff --git a/src/librustc_codegen_llvm/consts.rs b/src/librustc_codegen_llvm/consts.rs
index 72ff65361cada9d3e6974d100f27f1a61f2f76fe..21bf490beb0fb352c1d3168e5d3dca675d345ca8 100644 (file)
--- a/src/librustc_codegen_llvm/consts.rs
+++ b/src/librustc_codegen_llvm/consts.rs
@@ -66,16 +66,22 @@ pub fn addr_of_mut(
     cx: &CodegenCx<'ll, '_>,
     cv: &'ll Value,
     align: Align,
-    kind: &str,
+    kind: Option<&str>,
 ) -> &'ll Value {
     unsafe {
-        let name = cx.generate_local_symbol_name(kind);
-        let gv = declare::define_global(cx, &name[..], val_ty(cv)).unwrap_or_else(||{
-            bug!("symbol `{}` is already defined", name);
-        });
+        let gv = match kind {
+            Some(kind) if !cx.tcx.sess.fewer_names() => {
+                let name = cx.generate_local_symbol_name(kind);
+                let gv = declare::define_global(cx, &name[..], val_ty(cv)).unwrap_or_else(||{
+                    bug!("symbol `{}` is already defined", name);
+                });
+                llvm::LLVMRustSetLinkage(gv, llvm::Linkage::PrivateLinkage);
+                gv
+            },
+            _ => declare::define_private_global(cx, val_ty(cv)),
+        };
         llvm::LLVMSetInitializer(gv, cv);
         set_global_alignment(cx, gv, align);
-        llvm::LLVMRustSetLinkage(gv, llvm::Linkage::PrivateLinkage);
         SetUnnamedAddr(gv, true);
         gv
     }
@@ -85,7 +91,7 @@ pub fn addr_of(
     cx: &CodegenCx<'ll, '_>,
     cv: &'ll Value,
     align: Align,
-    kind: &str,
+    kind: Option<&str>,
 ) -> &'ll Value {
     if let Some(&gv) = cx.const_globals.borrow().get(&cv) {
         unsafe {

diff --git a/src/librustc_codegen_llvm/declare.rs b/src/librustc_codegen_llvm/declare.rs
index 9812d7f9a41a21cc81ad0642606fa13e700b4505..a0310eecd591d4f30da92605628f54eb4dfb34a5 100644 (file)
--- a/src/librustc_codegen_llvm/declare.rs
+++ b/src/librustc_codegen_llvm/declare.rs
@@ -35,7 +35,6 @@
 
 use std::ffi::CString;
 
-
 /// Declare a global value.
 ///
 /// If there’s a value with the same name already declared, the function will
@@ -170,6 +169,15 @@ pub fn define_global(cx: &CodegenCx<'ll, '_>, name: &str, ty: &'ll Type) -> Opti
     }
 }
 
+/// Declare a private global
+///
+/// Use this function when you intend to define a global without a name.
+pub fn define_private_global(cx: &CodegenCx<'ll, '_>, ty: &'ll Type) -> &'ll Value {
+    unsafe {
+        llvm::LLVMRustInsertPrivateGlobal(cx.llmod, ty)
+    }
+}
+
 /// Declare a Rust function with an intention to define it.
 ///
 /// Use this function when you intend to define a function. This function will

diff --git a/src/librustc_codegen_llvm/llvm/ffi.rs b/src/librustc_codegen_llvm/llvm/ffi.rs
index 989498ea92bcefd770af80cee557ac8f6741648b..a894f8e2fdb96a95686ceec3986ba3b4308870ba 100644 (file)
--- a/src/librustc_codegen_llvm/llvm/ffi.rs
+++ b/src/librustc_codegen_llvm/llvm/ffi.rs
@@ -623,6 +623,7 @@ pub fn LLVMConstExtractValue(AggConstant: &Value,
     pub fn LLVMAddGlobal(M: &'a Module, Ty: &'a Type, Name: *const c_char) -> &'a Value;
     pub fn LLVMGetNamedGlobal(M: &Module, Name: *const c_char) -> Option<&Value>;
     pub fn LLVMRustGetOrInsertGlobal(M: &'a Module, Name: *const c_char, T: &'a Type) -> &'a Value;
+    pub fn LLVMRustInsertPrivateGlobal(M: &'a Module, T: &'a Type) -> &'a Value;
     pub fn LLVMGetFirstGlobal(M: &Module) -> Option<&Value>;
     pub fn LLVMGetNextGlobal(GlobalVar: &Value) -> Option<&Value>;
     pub fn LLVMDeleteGlobal(GlobalVar: &Value);

diff --git a/src/librustc_codegen_llvm/meth.rs b/src/librustc_codegen_llvm/meth.rs
index 9c0dd0dc3d8b54f54e5409c381c7cdeb3d68467e..8a1159bc4773cfa4f231d309eb665cd1281044f4 100644 (file)
--- a/src/librustc_codegen_llvm/meth.rs
+++ b/src/librustc_codegen_llvm/meth.rs
@@ -106,7 +106,7 @@ pub fn get_vtable(
 
     let vtable_const = C_struct(cx, &components, false);
     let align = cx.data_layout().pointer_align;
-    let vtable = consts::addr_of(cx, vtable_const, align, "vtable");
+    let vtable = consts::addr_of(cx, vtable_const, align, Some("vtable"));
 
     debuginfo::create_vtable_metadata(cx, ty, vtable);
 

diff --git a/src/librustc_codegen_llvm/mir/block.rs b/src/librustc_codegen_llvm/mir/block.rs
index 684ecfaeec8f159d858f736e22b2d45b6a6699cd..4e389c3b915f011ebb4eb35a1f59dc2a2c7b7a45 100644 (file)
--- a/src/librustc_codegen_llvm/mir/block.rs
+++ b/src/librustc_codegen_llvm/mir/block.rs
@@ -377,7 +377,7 @@ fn codegen_terminator(&mut self,
                         let file_line_col = consts::addr_of(bx.cx,
                                                             file_line_col,
                                                             align,
-                                                            "panic_bounds_check_loc");
+                                                            Some("panic_bounds_check_loc"));
                         (lang_items::PanicBoundsCheckFnLangItem,
                          vec![file_line_col, index, len])
                     }
@@ -391,7 +391,7 @@ fn codegen_terminator(&mut self,
                         let msg_file_line_col = consts::addr_of(bx.cx,
                                                                 msg_file_line_col,
                                                                 align,
-                                                                "panic_loc");
+                                                                Some("panic_loc"));
                         (lang_items::PanicFnLangItem,
                          vec![msg_file_line_col])
                     }

diff --git a/src/librustc_codegen_llvm/mir/constant.rs b/src/librustc_codegen_llvm/mir/constant.rs
index 267db4467c21a23e376e7c89c9099404c000628d..a6e14a99f3c8eafe156d2756b59095c21cccc907 100644 (file)
--- a/src/librustc_codegen_llvm/mir/constant.rs
+++ b/src/librustc_codegen_llvm/mir/constant.rs
@@ -58,9 +58,9 @@ pub fn scalar_to_llvm(
                 Some(AllocType::Memory(alloc)) => {
                     let init = const_alloc_to_llvm(cx, alloc);
                     if alloc.runtime_mutability == Mutability::Mutable {
-                        consts::addr_of_mut(cx, init, alloc.align, "byte_str")
+                        consts::addr_of_mut(cx, init, alloc.align, None)
                     } else {
-                        consts::addr_of(cx, init, alloc.align, "byte_str")
+                        consts::addr_of(cx, init, alloc.align, None)
                     }
                 }
                 Some(AllocType::Function(fn_instance)) => {

diff --git a/src/librustc_codegen_llvm/mir/place.rs b/src/librustc_codegen_llvm/mir/place.rs
index abc3dbdab2f5b04d307bfce1424d717814499cf1..6fa0845dd0cebf14d45e56f5e6bcdf8b64675acf 100644 (file)
--- a/src/librustc_codegen_llvm/mir/place.rs
+++ b/src/librustc_codegen_llvm/mir/place.rs
@@ -63,7 +63,7 @@ pub fn from_const_alloc(
         offset: Size,
     ) -> PlaceRef<'ll, 'tcx> {
         let init = const_alloc_to_llvm(bx.cx, alloc);
-        let base_addr = consts::addr_of(bx.cx, init, layout.align, "byte_str");
+        let base_addr = consts::addr_of(bx.cx, init, layout.align, None);
 
         let llval = unsafe { LLVMConstInBoundsGEP(
             consts::bitcast(base_addr, Type::i8p(bx.cx)),

diff --git a/src/rustllvm/RustWrapper.cpp b/src/rustllvm/RustWrapper.cpp
index 4bcb4fd7ad385a4ec1c0db8593a65cb578d248e6..9b9c908ea52721ff3f5e4121e322541cbfd5fdab 100644 (file)
--- a/src/rustllvm/RustWrapper.cpp
+++ b/src/rustllvm/RustWrapper.cpp
@@ -12,6 +12,7 @@
 #include "llvm/IR/DebugInfoMetadata.h"
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/GlobalVariable.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/ObjectFile.h"
@@ -116,6 +117,15 @@ LLVMRustGetOrInsertGlobal(LLVMModuleRef M, const char *Name, LLVMTypeRef Ty) {
   return wrap(unwrap(M)->getOrInsertGlobal(Name, unwrap(Ty)));
 }
 
+extern "C" LLVMValueRef
+LLVMRustInsertPrivateGlobal(LLVMModuleRef M, LLVMTypeRef Ty) {
+  return wrap(new GlobalVariable(*unwrap(M),
+                                 unwrap(Ty),
+                                 false,
+                                 GlobalValue::PrivateLinkage,
+                                 nullptr));
+}
+
 extern "C" LLVMTypeRef LLVMRustMetadataTypeInContext(LLVMContextRef C) {
   return wrap(Type::getMetadataTy(*unwrap(C)));
 }

diff --git a/src/test/codegen/consts.rs b/src/test/codegen/consts.rs
index 30fffbb769b30dc2aa0484021446a1f4891cb585..301f5544486270b68cfa652b3e36c5e46be9dc73 100644 (file)
--- a/src/test/codegen/consts.rs
+++ b/src/test/codegen/consts.rs
@@ -21,11 +21,11 @@
 // CHECK: @STATIC = {{.*}}, align 4
 
 // This checks the constants from inline_enum_const
-// CHECK: @byte_str.{{[0-9]+}} = {{.*}}, align 2
+// CHECK: @{{[0-9]+}} = {{.*}}, align 2
 
 // This checks the constants from {low,high}_align_const, they share the same
 // constant, but the alignment differs, so the higher one should be used
-// CHECK: [[LOW_HIGH:@byte_str.[0-9]+]] = {{.*}}, align 4
+// CHECK: [[LOW_HIGH:@[0-9]+]] = {{.*}}, align 4
 
 #[derive(Copy, Clone)]
 

diff --git a/src/test/codegen/remap_path_prefix/main.rs b/src/test/codegen/remap_path_prefix/main.rs
index 4fb8c37558d48bbaa7ce1333709cbddf024bf8fa..dd0f89c931d8aa13d64374490584e4848875d1ac 100644 (file)
--- a/src/test/codegen/remap_path_prefix/main.rs
+++ b/src/test/codegen/remap_path_prefix/main.rs
@@ -22,7 +22,7 @@
 include!("aux_mod.rs");
 
 // Here we check that the expansion of the file!() macro is mapped.
-// CHECK: @byte_str.1 = private unnamed_addr constant <{ [34 x i8] }> <{ [34 x i8] c"/the/src/remap_path_prefix/main.rs" }>, align 1
+// CHECK: @0 = private unnamed_addr constant <{ [34 x i8] }> <{ [34 x i8] c"/the/src/remap_path_prefix/main.rs" }>, align 1
 pub static FILE_PATH: &'static str = file!();
 
 fn main() {

diff --git a/src/test/run-make-fulldeps/symbols-are-reasonable/Makefile b/src/test/run-make-fulldeps/symbols-are-reasonable/Makefile
deleted file mode 100644 (file)
index a6d294d..0000000
--- a/src/test/run-make-fulldeps/symbols-are-reasonable/Makefile
+++ /dev/null
@@ -1,13 +0,0 @@
--include ../tools.mk
-
-# check that the compile generated symbols for strings, binaries,
-# vtables, etc. have semisane names (e.g. `str.1234`); it's relatively
-# easy to accidentally modify the compiler internals to make them
-# become things like `str"str"(1234)`.
-
-OUT=$(TMPDIR)/lib.s
-
-all:
-       $(RUSTC) lib.rs --emit=asm --crate-type=staticlib
-       # just check for symbol declarations with the names we're expecting.
-       $(CGREP) -e 'str\.[0-9]+:' 'byte_str\.[0-9]+:' 'vtable\.[0-9]+' < $(OUT)

diff --git a/src/test/run-make-fulldeps/symbols-are-reasonable/lib.rs b/src/test/run-make-fulldeps/symbols-are-reasonable/lib.rs
deleted file mode 100644 (file)
index b9285b2..0000000
--- a/src/test/run-make-fulldeps/symbols-are-reasonable/lib.rs
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-pub static X: &'static str = "foobarbaz";
-pub static Y: &'static [u8] = include_bytes!("lib.rs");
-
-trait Foo { fn dummy(&self) { } }
-impl Foo for usize {}
-
-#[no_mangle]
-pub extern "C" fn dummy() {
-    // force the vtable to be created
-    let _x = &1usize as &Foo;
-}

diff --git a/src/test/run-pass-fulldeps/myriad-closures.rs b/src/test/run-pass-fulldeps/myriad-closures.rs
index a946ec635b29ffdccbdc8a56a4d959d9229230e7..baf27d6f57c3cda9c3c45953636b2e59eb9c1452 100644 (file)
--- a/src/test/run-pass-fulldeps/myriad-closures.rs
+++ b/src/test/run-pass-fulldeps/myriad-closures.rs
@@ -14,7 +14,7 @@
 // See https://github.com/rust-lang/rust/issues/34793 for more information.
 
 // Make sure we don't optimize anything away:
-// compile-flags: -C no-prepopulate-passes
+// compile-flags: -C no-prepopulate-passes -Cpasses=name-anon-globals
 
 // Expand something exponentially
 macro_rules! go_bacterial {

diff --git a/src/test/run-pass/issue-38226.rs b/src/test/run-pass/issue-38226.rs
index 33604212af9516c0357c7e7d6b1a53cfaa6ffb6d..dd9f9be7da713de4bfa956db02e81f85c161a843 100644 (file)
--- a/src/test/run-pass/issue-38226.rs
+++ b/src/test/run-pass/issue-38226.rs
@@ -15,7 +15,7 @@
 
 // Need -Cno-prepopulate-passes to really disable inlining, otherwise the faulty
 // code gets optimized out:
-// compile-flags: -Cno-prepopulate-passes
+// compile-flags: -Cno-prepopulate-passes -Cpasses=name-anon-globals
 
 extern crate issue_38226_aux;
 

diff --git a/src/test/ui/feature-gate-unwind-attributes.rs b/src/test/ui/feature-gate-unwind-attributes.rs
index c8f9cd943cdaaf9ab61d41e2b71cc1faefbef3e0..681842e30e006c8ea1415a112a59d7c2465c3e0f 100644 (file)
--- a/src/test/ui/feature-gate-unwind-attributes.rs
+++ b/src/test/ui/feature-gate-unwind-attributes.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// compile-flags: -C no-prepopulate-passes
+// compile-flags: -C no-prepopulate-passes -Cpasses=name-anon-globals
 
 #![crate_type = "lib"]