Merge commit 'dbee13661efa269cb4cd57bb4c6b99a19732b484' into sync_cg_clif-2020-12-27

[rust.git] / compiler / rustc_codegen_cranelift / src / base.rs

diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs
index 72073896a723b89f908879e70e15be35c68f17b5..34c9561d6762287a6113ee700e4042e6041b4352 100644 (file)
--- a/compiler/rustc_codegen_cranelift/src/base.rs
+++ b/compiler/rustc_codegen_cranelift/src/base.rs
@@ -118,6 +118,8 @@ pub(crate) fn codegen_fn<'tcx>(
     context.eliminate_unreachable_code(cx.module.isa()).unwrap();
     context.dce(cx.module.isa()).unwrap();
 
+    context.want_disasm = crate::pretty_clif::should_write_ir(tcx);
+
     // Define function
     let module = &mut cx.module;
     tcx.sess.time("define function", || {
@@ -140,6 +142,16 @@ pub(crate) fn codegen_fn<'tcx>(
         &clif_comments,
     );
 
+    if let Some(mach_compile_result) = &context.mach_compile_result {
+        if let Some(disasm) = &mach_compile_result.disasm {
+            crate::pretty_clif::write_ir_file(
+                tcx,
+                &format!("{}.vcode", tcx.symbol_name(instance).name),
+                |file| file.write_all(disasm.as_bytes()),
+            )
+        }
+    }
+
     // Define debuginfo for function
     let isa = cx.module.isa();
     let debug_context = &mut cx.debug_context;
@@ -307,7 +319,9 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Module>) {
             } => {
                 let discr = codegen_operand(fx, discr).load_scalar(fx);
 
-                if switch_ty.kind() == fx.tcx.types.bool.kind() {
+                let use_bool_opt = switch_ty.kind() == fx.tcx.types.bool.kind()
+                    || (targets.iter().count() == 1 && targets.iter().next().unwrap().0 == 0);
+                if use_bool_opt {
                     assert_eq!(targets.iter().count(), 1);
                     let (then_value, then_block) = targets.iter().next().unwrap();
                     let then_block = fx.get_block(then_block);
@@ -325,12 +339,22 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Module>) {
                     let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
                     let discr =
                         crate::optimize::peephole::make_branchable_value(&mut fx.bcx, discr);
-                    if test_zero {
-                        fx.bcx.ins().brz(discr, then_block, &[]);
-                        fx.bcx.ins().jump(else_block, &[]);
+                    if let Some(taken) = crate::optimize::peephole::maybe_known_branch_taken(
+                        &fx.bcx, discr, test_zero,
+                    ) {
+                        if taken {
+                            fx.bcx.ins().jump(then_block, &[]);
+                        } else {
+                            fx.bcx.ins().jump(else_block, &[]);
+                        }
                     } else {
-                        fx.bcx.ins().brnz(discr, then_block, &[]);
-                        fx.bcx.ins().jump(else_block, &[]);
+                        if test_zero {
+                            fx.bcx.ins().brz(discr, then_block, &[]);
+                            fx.bcx.ins().jump(else_block, &[]);
+                        } else {
+                            fx.bcx.ins().brnz(discr, then_block, &[]);
+                            fx.bcx.ins().jump(else_block, &[]);
+                        }
                     }
                 } else {
                     let mut switch = ::cranelift_frontend::Switch::new();