Simplify bitcode embedding - either None or Full

Author: thombles

src/librustc_codegen_llvm/back/write.rs

@@ -651,10 +651,8 @@ pub(crate) unsafe fn codegen(
                     "LLVM_module_codegen_embed_bitcode",
                     &module.name[..],
                 );
-                embed_bitcode(cgcx, llcx, llmod, &config.bc_cmdline, Some(data));
+                embed_bitcode(cgcx, llcx, llmod, &config.bc_cmdline, data);
             }
-        } else if config.emit_obj == EmitObj::ObjectCode(BitcodeSection::Marker) {
-            embed_bitcode(cgcx, llcx, llmod, &config.bc_cmdline, None);
         }
 
         if config.emit_ir {
@@ -790,9 +788,9 @@ unsafe fn embed_bitcode(
     llcx: &llvm::Context,
     llmod: &llvm::Module,
     cmdline: &str,
-    bitcode: Option<&[u8]>,
+    bitcode: &[u8],
 ) {
-    let llconst = common::bytes_in_context(llcx, bitcode.unwrap_or(&[]));
+    let llconst = common::bytes_in_context(llcx, bitcode);
     let llglobal = llvm::LLVMAddGlobal(
         llmod,
         common::val_ty(llconst),

src/librustc_codegen_ssa/back/write.rs

@@ -68,10 +68,6 @@ pub enum BitcodeSection {
     // No bitcode section.
     None,
 
-    // An empty bitcode section (to placate tools such as the iOS linker that
-    // require this section even if they don't use it).
-    Marker,
-
     // A full, uncompressed bitcode section.
     Full,
 }
@@ -148,16 +144,8 @@ impl ModuleConfig {
             || sess.opts.cg.linker_plugin_lto.enabled()
         {
             EmitObj::Bitcode
-        } else if sess.target.target.options.forces_embed_bitcode {
+        } else if need_bitcode_in_object(sess) {
             EmitObj::ObjectCode(BitcodeSection::Full)
-        } else if need_crate_bitcode_for_rlib(sess) {
-            let force_full = need_crate_bitcode_for_rlib(sess);
-            match sess.opts.optimize {
-                config::OptLevel::No | config::OptLevel::Less if !force_full => {
-                    EmitObj::ObjectCode(BitcodeSection::Marker)
-                }
-                _ => EmitObj::ObjectCode(BitcodeSection::Full),
-            }
         } else {
             EmitObj::ObjectCode(BitcodeSection::None)
         };
@@ -376,10 +364,12 @@ pub struct CompiledModules {
     pub allocator_module: Option<CompiledModule>,
 }
 
-fn need_crate_bitcode_for_rlib(sess: &Session) -> bool {
-    sess.opts.cg.embed_bitcode
+fn need_bitcode_in_object(sess: &Session) -> bool {
+    let requested_for_rlib = sess.opts.cg.embed_bitcode
         && sess.crate_types.borrow().contains(&CrateType::Rlib)
-        && sess.opts.output_types.contains_key(&OutputType::Exe)
+        && sess.opts.output_types.contains_key(&OutputType::Exe);
+    let forced_by_target = sess.target.target.options.forces_embed_bitcode;
+    requested_for_rlib || forced_by_target
 }
 
 fn need_pre_lto_bitcode_for_incr_comp(sess: &Session) -> bool {