From 7d59fb4661e02ab28a42348c317d12a223db3cc5 Mon Sep 17 00:00:00 2001
From: Mark McCaskey <mark@wasmer.io>
Date: Tue, 24 Mar 2020 14:47:00 -0700
Subject: [PATCH] Add `CompilerConifg` opt to disable IR verification in debug
 mode

---
 lib/clif-backend/src/lib.rs        | 16 +++++++++++-----
 lib/clif-backend/src/trampoline.rs | 16 ++++++++--------
 lib/runtime-core/src/backend.rs    |  6 ++++++
 3 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/lib/clif-backend/src/lib.rs b/lib/clif-backend/src/lib.rs
index c4fb65736c3..02bf479aad7 100644
--- a/lib/clif-backend/src/lib.rs
+++ b/lib/clif-backend/src/lib.rs
@@ -43,16 +43,22 @@ fn get_isa(config: Option<&CompilerConfig>) -> Box<dyn isa::TargetIsa> {
         builder.set("opt_level", "speed_and_size").unwrap();
         builder.set("enable_jump_tables", "false").unwrap();
 
-        if cfg!(test) || cfg!(debug_assertions) {
-            builder.set("enable_verifier", "true").unwrap();
-        } else {
-            builder.set("enable_verifier", "false").unwrap();
-        }
+        let enable_verifier: bool;
 
         if let Some(config) = config {
             if config.nan_canonicalization {
                 builder.set("enable_nan_canonicalization", "true").unwrap();
             }
+            enable_verifier = !config.disable_debug_mode_verification;
+        } else {
+            // Set defaults if no config found.
+            enable_verifier = true;
+        }
+
+        if (cfg!(test) || cfg!(debug_assertions)) && enable_verifier {
+            builder.set("enable_verifier", "true").unwrap();
+        } else {
+            builder.set("enable_verifier", "false").unwrap();
         }
 
         let flags = settings::Flags::new(builder);
diff --git a/lib/clif-backend/src/trampoline.rs b/lib/clif-backend/src/trampoline.rs
index 6b6c5d7ea08..b792f95c285 100644
--- a/lib/clif-backend/src/trampoline.rs
+++ b/lib/clif-backend/src/trampoline.rs
@@ -86,7 +86,7 @@ impl Trampolines {
             let sig_index = module.func_assoc[*exported_func_index];
             let func_sig = &module.signatures[sig_index];
 
-            let trampoline_func = generate_func(&func_sig);
+            let trampoline_func = generate_func(isa, &func_sig);
 
             ctx.func = trampoline_func;
 
@@ -150,13 +150,13 @@ impl Trampolines {
 
 /// This function generates a trampoline for the specific signature
 /// passed into it.
-fn generate_func(func_sig: &FuncSig) -> ir::Function {
-    let trampoline_sig = generate_trampoline_signature();
+fn generate_func(isa: &dyn isa::TargetIsa, func_sig: &FuncSig) -> ir::Function {
+    let trampoline_sig = generate_trampoline_signature(isa);
 
     let mut func =
         ir::Function::with_name_signature(ir::ExternalName::testcase("trampln"), trampoline_sig);
 
-    let export_sig_ref = func.import_signature(generate_export_signature(func_sig));
+    let export_sig_ref = func.import_signature(generate_export_signature(isa, func_sig));
 
     let entry_ebb = func.dfg.make_block();
     let vmctx_ptr = func.dfg.append_block_param(entry_ebb, ir::types::I64);
@@ -211,8 +211,8 @@ fn wasm_ty_to_clif(ty: Type) -> ir::types::Type {
     }
 }
 
-fn generate_trampoline_signature() -> ir::Signature {
-    let call_convention = super::get_isa(None).default_call_conv();
+fn generate_trampoline_signature(isa: &dyn isa::TargetIsa) -> ir::Signature {
+    let call_convention = isa.default_call_conv();
     let mut sig = ir::Signature::new(call_convention);
 
     let ptr_param = ir::AbiParam {
@@ -227,8 +227,8 @@ fn generate_trampoline_signature() -> ir::Signature {
     sig
 }
 
-fn generate_export_signature(func_sig: &FuncSig) -> ir::Signature {
-    let call_convention = super::get_isa(None).default_call_conv();
+fn generate_export_signature(isa: &dyn isa::TargetIsa, func_sig: &FuncSig) -> ir::Signature {
+    let call_convention = isa.default_call_conv();
     let mut export_clif_sig = ir::Signature::new(call_convention);
 
     let func_sig_iter = func_sig.params().iter().map(|wasm_ty| ir::AbiParam {
diff --git a/lib/runtime-core/src/backend.rs b/lib/runtime-core/src/backend.rs
index eabe526d8c7..2b0f54c4f0a 100644
--- a/lib/runtime-core/src/backend.rs
+++ b/lib/runtime-core/src/backend.rs
@@ -136,6 +136,12 @@ pub struct CompilerConfig {
     /// Enabling this makes execution deterministic but increases runtime overhead.
     pub nan_canonicalization: bool,
 
+    /// Turns off verification that is done by default when `debug_assertions` are enabled
+    /// (for example in 'debug' builds). Enabling this flag will make compilation faster at the
+    /// cost of not detecting bugs in the compiler. The verification steps that this flag
+    /// disables are disabled by default in 'release' builds.
+    pub disable_debug_mode_verification: bool,
+
     pub features: Features,
 
     // Target info. Presently only supported by LLVM.