Merge #898

898: Disable track-state by default, disable @llvm.experimental.stackmap emission in the LLVM backend when it's disabled. r=nlewycky a=nlewycky



Co-authored-by: Nick Lewycky <nick@wasmer.io>

lib/llvm-backend/src/code.rs

@@ -15,7 +15,7 @@ use std::cell::RefCell;
 use std::rc::Rc;
 use std::sync::{Arc, RwLock};
 use wasmer_runtime_core::{
-    backend::{Backend, CacheGen, Token},
+    backend::{Backend, CacheGen, CompilerConfig, Token},
     cache::{Artifact, Error as CacheError},
     codegen::*,
     memory::MemoryType,
@@ -676,6 +676,7 @@ pub struct LLVMModuleCodeGenerator {
     personality_func: FunctionValue,
     module: Module,
     stackmaps: Rc<RefCell<StackmapRegistry>>,
+    track_state: bool,
 }
 
 pub struct LLVMFunctionCodeGenerator {
@@ -693,6 +694,7 @@ pub struct LLVMFunctionCodeGenerator {
     stackmaps: Rc<RefCell<StackmapRegistry>>,
     index: usize,
     opcode_offset: usize,
+    track_state: bool,
 }
 
 impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
@@ -768,6 +770,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
             let builder = self.builder.as_ref().unwrap();
             let intrinsics = self.intrinsics.as_ref().unwrap();
 
+            if self.track_state {
                 let mut stackmaps = self.stackmaps.borrow_mut();
                 emit_stack_map(
                     &module_info,
@@ -790,6 +793,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                     ::std::usize::MAX,
                 );
             }
+        }
 
         Ok(())
     }
@@ -918,6 +922,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
 
                 builder.position_at_end(&loop_body);
 
+                if self.track_state {
                     if let Some(offset) = opcode_offset {
                         let mut stackmaps = self.stackmaps.borrow_mut();
                         emit_stack_map(
@@ -946,6 +951,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                             offset,
                         );
                     }
+                }
 
                 state.push_loop(loop_body, loop_next, phis);
             }
@@ -1215,6 +1221,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                 // Comment out this `if` block to allow spectests to pass.
                 // TODO: fix this
                 if let Some(offset) = opcode_offset {
+                    if self.track_state {
                         let mut stackmaps = self.stackmaps.borrow_mut();
                         emit_stack_map(
                             &info,
@@ -1238,6 +1245,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                             offset,
                         );
                     }
+                }
 
                 builder.build_call(
                     intrinsics.throw_trap,
@@ -1495,6 +1503,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                 };
 
                 state.popn(func_sig.params().len())?;
+                if self.track_state {
                     if let Some(offset) = opcode_offset {
                         let mut stackmaps = self.stackmaps.borrow_mut();
                         emit_stack_map(
@@ -1510,7 +1519,9 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                             offset,
                         )
                     }
+                }
                 let call_site = builder.build_call(func_ptr, &params, &state.var_name());
+                if self.track_state {
                     if let Some(offset) = opcode_offset {
                         let mut stackmaps = self.stackmaps.borrow_mut();
                         finalize_opcode_stack_map(
@@ -1522,6 +1533,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                             offset,
                         )
                     }
+                }
 
                 if let Some(basic_value) = call_site.try_as_basic_value().left() {
                     match func_sig.returns().len() {
@@ -1704,6 +1716,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                     "typed_func_ptr",
                 );
 
+                if self.track_state {
                     if let Some(offset) = opcode_offset {
                         let mut stackmaps = self.stackmaps.borrow_mut();
                         emit_stack_map(
@@ -1719,7 +1732,9 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                             offset,
                         )
                     }
+                }
                 let call_site = builder.build_call(typed_func_ptr, &args, "indirect_call");
+                if self.track_state {
                     if let Some(offset) = opcode_offset {
                         let mut stackmaps = self.stackmaps.borrow_mut();
                         finalize_opcode_stack_map(
@@ -1731,6 +1746,7 @@ impl FunctionCodeGenerator<CodegenError> for LLVMFunctionCodeGenerator {
                             offset,
                         )
                     }
+                }
 
                 match wasmer_fn_sig.returns() {
                     [] => {}
@@ -7242,6 +7258,7 @@ impl ModuleCodeGenerator<LLVMFunctionCodeGenerator, LLVMBackend, CodegenError>
             func_import_count: 0,
             personality_func,
             stackmaps: Rc::new(RefCell::new(StackmapRegistry::default())),
+            track_state: false,
         }
     }
 
@@ -7341,6 +7358,7 @@ impl ModuleCodeGenerator<LLVMFunctionCodeGenerator, LLVMBackend, CodegenError>
             stackmaps: self.stackmaps.clone(),
             index: local_func_index,
             opcode_offset: 0,
+            track_state: self.track_state,
         };
         self.functions.push(code);
         Ok(self.functions.last_mut().unwrap())
@@ -7416,6 +7434,11 @@ impl ModuleCodeGenerator<LLVMFunctionCodeGenerator, LLVMBackend, CodegenError>
         Ok((backend, Box::new(cache_gen)))
     }
 
+    fn feed_compiler_config(&mut self, config: &CompilerConfig) -> Result<(), CodegenError> {
+        self.track_state = config.track_state;
+        Ok(())
+    }
+
     fn feed_signatures(&mut self, signatures: Map<SigIndex, FuncSig>) -> Result<(), CodegenError> {
         self.signatures = signatures
             .iter()

src/bin/wasmer.rs

@@ -177,8 +177,8 @@ struct Run {
 
     /// Whether or not state tracking should be disabled during compilation.
     /// State tracking is necessary for tier switching and backtracing.
-    #[structopt(long = "no-track-state")]
+    #[structopt(long = "track-state")]
-    no_track_state: bool,
+    track_state: bool,
 
     /// The command name is a string that will override the first argument passed
     /// to the wasm program. This is used in wapm to provide nicer output in
@@ -419,7 +419,7 @@ fn execute_wasm(options: &Run) -> Result<(), String> {
         }
     }
 
-    let track_state = !options.no_track_state;
+    let track_state = options.track_state;
 
     #[cfg(feature = "loader-kernel")]
     let is_kernel_loader = if let Some(LoaderName::Kernel) = options.loader {