Auto merge of rust-lang#127513 - nikic:llvm-19, r=cuviper

Update to LLVM 19

The LLVM 19.1.0 final release is planned for Sep 3rd. The rustc 1.82 stable release will be on Oct 17th.

The unstable MC/DC coverage support is temporarily broken by this update. It will be restored by rust-lang#126733. The implementation changed substantially in LLVM 19, and there are no plans to support both the LLVM 18 and LLVM 19 implementation at the same time.

Compatibility note for wasm:

> WebAssembly target support for the `multivalue` target feature has changed when upgrading to LLVM 19. Support for generating functions with multiple returns no longer works and `-Ctarget-feature=+multivalue` has a different meaning than it did in LLVM 18 and prior. The WebAssembly target features `multivalue` and `reference-types` are now both enabled by default, but generated code is not affected by default. These features being enabled are encoded in the `target_features` custom section and may affect downstream tooling such as `wasm-opt` consuming the module, but the actual generated WebAssembly will continue to not use either `multivalue` or `reference-types` by default. There is no longer any supported means to generate a module that has a function with multiple returns.

Related changes:
 * rust-lang#127605
 * rust-lang#127613
 * rust-lang#127654
 * rust-lang#128141
 * llvm/llvm-project#98933

Fixes rust-lang#121444.
Fixes rust-lang#128212.

Author: bors

.gitmodules

@@ -33,7 +33,7 @@
 [submodule "src/llvm-project"]
 	path = src/llvm-project
 	url = https://github.com/rust-lang/llvm-project.git
-	branch = rustc/18.1-2024-05-19
+	branch = rustc/19.1-2024-07-30
 	shallow = true
 [submodule "src/doc/embedded-book"]
 	path = src/doc/embedded-book

compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp

@@ -1555,7 +1555,7 @@ LLVMRustGetInstrProfMCDCTVBitmapUpdateIntrinsic(LLVMModuleRef M) {
 
 extern "C" LLVMValueRef
 LLVMRustGetInstrProfMCDCCondBitmapIntrinsic(LLVMModuleRef M) {
-#if LLVM_VERSION_GE(18, 0)
+#if LLVM_VERSION_GE(18, 0) && LLVM_VERSION_LT(19, 0)
   return wrap(llvm::Intrinsic::getDeclaration(
       unwrap(M), llvm::Intrinsic::instrprof_mcdc_condbitmap_update));
 #else

src/llvm-project

@@ -1,6 +1,7 @@
 #![feature(coverage_attribute)]
 //@ edition: 2021
 //@ min-llvm-version: 18
+//@ ignore-llvm-version: 19 - 99
 //@ compile-flags: -Zcoverage-options=mcdc
 //@ llvm-cov-flags: --show-branches=count --show-mcdc
 

tests/coverage/mcdc/condition-limit.rs

@@ -1,6 +1,7 @@
 #![feature(coverage_attribute)]
 //@ edition: 2021
 //@ min-llvm-version: 18
+//@ ignore-llvm-version: 19 - 99
 //@ compile-flags: -Zcoverage-options=mcdc
 //@ llvm-cov-flags: --show-branches=count --show-mcdc
 

tests/coverage/mcdc/if.rs

@@ -1,6 +1,7 @@
 #![feature(coverage_attribute)]
 //@ edition: 2021
 //@ min-llvm-version: 18
+//@ ignore-llvm-version: 19 - 99
 //@ compile-flags: -Zcoverage-options=mcdc -Copt-level=z -Cllvm-args=--inline-threshold=0
 //@ llvm-cov-flags: --show-branches=count --show-mcdc
 

tests/coverage/mcdc/inlined_expressions.rs

@@ -1,6 +1,7 @@
 #![feature(coverage_attribute)]
 //@ edition: 2021
 //@ min-llvm-version: 18
+//@ ignore-llvm-version: 19 - 99
 //@ compile-flags: -Zcoverage-options=mcdc
 //@ llvm-cov-flags: --show-branches=count --show-mcdc
 

tests/coverage/mcdc/nested_if.rs

@@ -1,6 +1,7 @@
 #![feature(coverage_attribute)]
 //@ edition: 2021
 //@ min-llvm-version: 18
+//@ ignore-llvm-version: 19 - 99
 //@ compile-flags: -Zcoverage-options=mcdc
 //@ llvm-cov-flags: --show-branches=count --show-mcdc
 

tests/coverage/mcdc/non_control_flow.rs

@@ -1,11 +1,13 @@
-//@ known-bug: #121444
 //@ compile-flags: -Copt-level=0
-//@ edition:2021
 //@ only-x86_64
 //@ ignore-windows
+//@ min-llvm-version: 19
+//@ build-pass
+
 #[repr(align(536870912))]
 pub struct A(i64);
 
+#[allow(improper_ctypes_definitions)]
 pub extern "C" fn foo(x: A) {}
 
 fn main() {