[wip] let backend know about exception flow. also add one more test to see if...

[wip] let backend know about exception flow. also add one more test to see if callee-saved register is restored
during catching exception, the test failed (and I marked it as ignored).

src/ast/src/inst.rs

@@ -2,6 +2,7 @@ use ir::*;
 use ptr::*;
 use types::*;
 use op::*;
+use ir_semantics;
 
 use utils::vec_utils;
 
@@ -68,6 +69,63 @@ impl Clone for Instruction {
 }
 
 impl Instruction {
+    pub fn has_exception_clause(&self) -> bool {
+        ir_semantics::is_potentially_excepting_instruction(&self.v)
+    }
+
+    pub fn get_exception_target(&self) -> Option<MuID> {
+        use inst::Instruction_::*;
+        match self.v {
+            Watchpoint {ref resume, ..}
+            | Call {ref resume, ..}
+            | CCall {ref resume, ..}
+            | SwapStack {ref resume, ..}
+            | ExnInstruction {ref resume, ..} => {
+                Some(resume.exn_dest.target)
+            },
+
+            BinOp(_, _, _)
+            | BinOpWithStatus(_, _, _, _)
+            | CmpOp(_, _, _)
+            | ConvOp{..}
+            | ExprCall{..}
+            | ExprCCall{..}
+            | Load{..}
+            | Store{..}
+            | CmpXchg{..}
+            | AtomicRMW{..}
+            | New(_)
+            | AllocA(_)
+            | NewHybrid(_, _)
+            | AllocAHybrid(_, _)
+            | NewStack(_)
+            | NewThread(_, _)
+            | NewThreadExn(_, _)
+            | NewFrameCursor(_)
+            | GetIRef(_)
+            | GetFieldIRef{..}
+            | GetElementIRef{..}
+            | ShiftIRef{..}
+            | GetVarPartIRef{..}
+            | Fence(_)
+            | Return(_)
+            | ThreadExit
+            | Throw(_)
+            | TailCall(_)
+            | Branch1(_)
+            | Branch2{..}
+            | Select{..}
+            | WPBranch{..}
+            | Switch{..}
+            | CommonInst_GetThreadLocal
+            | CommonInst_SetThreadLocal(_)
+            | CommonInst_Pin(_)
+            | CommonInst_Unpin(_)
+            | Move(_)
+            | PrintHex(_) => None
+        }
+    }
+
     fn debug_str(&self, ops: &Vec<P<TreeNode>>) -> String {
         self.v.debug_str(ops)
     }

src/ast/src/ir_semantics.rs

@@ -103,3 +103,53 @@ pub fn has_side_effect(inst: &Instruction_) -> bool {
         &PrintHex(_) => true
     }
 }
+
+pub fn is_potentially_excepting_instruction(inst: &Instruction_) -> bool {
+    match inst {
+        &Watchpoint{..}
+        | &Call{..}
+        | &CCall{..}
+        | &SwapStack{..}
+        | &ExnInstruction{..} => true,
+
+        &BinOp(_, _, _)
+        | &BinOpWithStatus(_, _, _, _)
+        | &CmpOp(_, _, _)
+        | &ConvOp{..}
+        | &ExprCall{..}
+        | &ExprCCall{..}
+        | &Load{..}
+        | &Store{..}
+        | &CmpXchg{..}
+        | &AtomicRMW{..}
+        | &New(_)
+        | &AllocA(_)
+        | &NewHybrid(_, _)
+        | &AllocAHybrid(_, _)
+        | &NewStack(_)
+        | &NewThread(_, _)
+        | &NewThreadExn(_, _)
+        | &NewFrameCursor(_)
+        | &GetIRef(_)
+        | &GetFieldIRef{..}
+        | &GetElementIRef{..}
+        | &ShiftIRef{..}
+        | &GetVarPartIRef{..}
+        | &Fence(_)
+        | &Return(_)
+        | &ThreadExit
+        | &Throw(_)
+        | &TailCall(_)
+        | &Branch1(_)
+        | &Branch2{..}
+        | &Select{..}
+        | &WPBranch{..}
+        | &Switch{..}
+        | &CommonInst_GetThreadLocal
+        | &CommonInst_SetThreadLocal(_)
+        | &CommonInst_Pin(_)
+        | &CommonInst_Unpin(_)
+        | &Move(_)
+        | &PrintHex(_) => false
+    }
+}
\ No newline at end of file

src/compiler/backend/arch/x86_64/asm_backend.rs

@@ -376,6 +376,35 @@ impl ASMCode {
                         panic!("conditional branch does not have a fallthrough target");
                     }
                 },
+                ASMBranchTarget::PotentiallyExcepting(ref target) => {
+                    // may trigger exception and jump to target - similar as conditional branch
+                    let target_n = self.blocks.get(target).unwrap().start_inst;
+
+                    // cur inst's succ is target
+                    asm[i].succs.push(target_n);
+
+                    if TRACE_CFA {
+                        trace!("inst {}: is potentially excepting to {}", i, target);
+                        trace!("inst {}: excepting target index is {}", i, target_n);
+                        trace!("inst {}: set SUCCS as excepting target {}", i, target_n);
+                    }
+
+                    asm[target_n].preds.push(i);
+
+                    if let Some(next_inst) = ASMCode::find_next_inst(i, asm) {
+                        // cur succ is next inst
+                        asm[i].succs.push(next_inst);
+
+                        // next inst's pred is cur
+                        asm[next_inst].preds.push(i);
+
+                        if TRACE_CFA {
+                            trace!("inst {}: SET SUCCS as PEI fallthrough target {}", i, next_inst);
+                        }
+                    } else {
+                        panic!("PEI does not have a fallthrough target");
+                    }
+                },
                 ASMBranchTarget::Return => {
                     if TRACE_CFA {
                         trace!("inst {}: is a return", i);
@@ -436,6 +465,27 @@ impl ASMCode {
         }
     }
 
+    fn find_last_inst(i: usize, asm: &Vec<ASMInst>) -> Option<usize> {
+        if i == 0 {
+            None
+        } else {
+            let mut cur = i;
+            while cur >= 0 {
+                if !asm[cur].is_symbol {
+                    return Some(cur);
+                }
+
+                if cur == 0 {
+                    return None;
+                } else {
+                    cur -= 1;
+                }
+            }
+
+            None
+        }
+    }
+
     fn add_frame_size_patchpoint(&mut self, patchpoint: ASMLocation) {
         self.frame_size_patchpoints.push(patchpoint);
     }
@@ -680,6 +730,10 @@ impl MachineCode for ASMCode {
         let mut ret = vec![];
         
         for inst in self.code.iter() {
+            if !inst.is_symbol {
+                ret.append(&mut "\t".to_string().into_bytes());
+            }
+
             ret.append(&mut inst.code.clone().into_bytes());
             ret.append(&mut "\n".to_string().into_bytes());
         }
@@ -744,6 +798,14 @@ impl MachineCode for ASMCode {
             None => None
         }
     }
+
+    fn get_next_inst(&self, index: usize) -> Option<usize> {
+        ASMCode::find_next_inst(index, &self.code)
+    }
+
+    fn get_last_inst(&self, index: usize) -> Option<usize> {
+        ASMCode::find_last_inst(index, &self.code)
+    }
 }
 
 #[derive(Clone, Debug)]
@@ -751,6 +813,7 @@ enum ASMBranchTarget {
     None,
     Conditional(MuName),
     Unconditional(MuName),
+    PotentiallyExcepting(MuName),
     Return
 }
 
@@ -930,7 +993,7 @@ impl ASMCodeGen {
         regs.map(|x| self.prepare_machine_reg(x)).collect()
     }
     
-    fn add_asm_call(&mut self, code: String) {
+    fn add_asm_call(&mut self, code: String, potentially_excepting: Option<MuName>) {
         // a call instruction will use all the argument registers
         // do not need
         let uses : LinkedHashMap<MuID, Vec<ASMLocation>> = LinkedHashMap::new();
@@ -960,7 +1023,13 @@ impl ASMCodeGen {
             }
         }
           
-        self.add_asm_inst(code, defines, uses, false);
+        self.add_asm_inst_internal(code, defines, uses, false, {
+            if potentially_excepting.is_some() {
+                ASMBranchTarget::PotentiallyExcepting(potentially_excepting.unwrap())
+            } else {
+                ASMBranchTarget::None
+            }
+        }, None)
     }
     
     fn add_asm_ret(&mut self, code: String) {
@@ -2703,11 +2772,11 @@ impl CodeGenerator for ASMCodeGen {
     }    
 
     #[cfg(target_os = "macos")]
-    fn emit_call_near_rel32(&mut self, callsite: String, func: MuName) -> ValueLocation {
+    fn emit_call_near_rel32(&mut self, callsite: String, func: MuName, pe: Option<MuName>) -> ValueLocation {
         trace!("emit: call {}", func);
         
         let asm = format!("call {}", symbol(func));
-        self.add_asm_call(asm);
+        self.add_asm_call(asm, pe);
         
         let callsite_symbol = symbol(callsite.clone());
         self.add_asm_symbolic(directive_globl(callsite_symbol.clone()));
@@ -2718,13 +2787,13 @@ impl CodeGenerator for ASMCodeGen {
 
     #[cfg(target_os = "linux")]
     // generating Position-Independent Code using PLT
-    fn emit_call_near_rel32(&mut self, callsite: String, func: MuName) -> ValueLocation {
+    fn emit_call_near_rel32(&mut self, callsite: String, func: MuName, pe: Option<MuName>) -> ValueLocation {
         trace!("emit: call {}", func);
 
         let func = func + "@PLT";
 
         let asm = format!("call {}", symbol(func));
-        self.add_asm_call(asm);
+        self.add_asm_call(asm, pe);
 
         let callsite_symbol = symbol(callsite.clone());
         self.add_asm_symbolic(directive_globl(callsite_symbol.clone()));
@@ -2733,12 +2802,12 @@ impl CodeGenerator for ASMCodeGen {
         ValueLocation::Relocatable(RegGroup::GPR, callsite)
     }
     
-    fn emit_call_near_r64(&mut self, callsite: String, func: &P<Value>) -> ValueLocation {
+    fn emit_call_near_r64(&mut self, callsite: String, func: &P<Value>, pe: Option<MuName>) -> ValueLocation {
         trace!("emit: call {}", func);
         unimplemented!()
     }
     
-    fn emit_call_near_mem64(&mut self, callsite: String, func: &P<Value>) -> ValueLocation {
+    fn emit_call_near_mem64(&mut self, callsite: String, func: &P<Value>, pe: Option<MuName>) -> ValueLocation {
         trace!("emit: call {}", func);
         unimplemented!()
     }

src/compiler/backend/arch/x86_64/codegen.rs

@@ -163,9 +163,9 @@ pub trait CodeGenerator {
     fn emit_jl(&mut self, dest: MuName);
     fn emit_jle(&mut self, dest: MuName);
     
-    fn emit_call_near_rel32(&mut self, callsite: String, func: MuName) -> ValueLocation;
-    fn emit_call_near_r64(&mut self, callsite: String, func: &P<Value>) -> ValueLocation;
-    fn emit_call_near_mem64(&mut self, callsite: String, func: &P<Value>) -> ValueLocation;
+    fn emit_call_near_rel32(&mut self, callsite: String, func: MuName,    pe: Option<MuName>) -> ValueLocation;
+    fn emit_call_near_r64  (&mut self, callsite: String, func: &P<Value>, pe: Option<MuName>) -> ValueLocation;
+    fn emit_call_near_mem64(&mut self, callsite: String, func: &P<Value>, pe: Option<MuName>) -> ValueLocation;
     
     fn emit_ret(&mut self);
 

src/compiler/backend/arch/x86_64/inst_sel.rs

@@ -2384,7 +2384,7 @@ impl <'a> InstructionSelection {
             unimplemented!()
         } else {
             let callsite = self.new_callsite_label(cur_node);
-            self.backend.emit_call_near_rel32(callsite, func_name);
+            self.backend.emit_call_near_rel32(callsite, func_name, None); // assume ccall wont throw exception
             
             // record exception block (CCall may have an exception block)
             if cur_node.is_some() {
@@ -2512,6 +2512,16 @@ impl <'a> InstructionSelection {
             }
         }
         let stack_arg_size = self.emit_precall_convention(&arg_values, vm);
+
+        // check if this call has exception clause - need to tell backend about this
+        let potentially_excepting = {
+            if resumption.is_some() {
+                let target_id = resumption.unwrap().exn_dest.target;
+                Some(f_content.get_block(target_id).name().unwrap())
+            } else {
+                None
+            }
+        };
         
         trace!("generating call inst");
         // check direct call or indirect
@@ -2525,18 +2535,18 @@ impl <'a> InstructionSelection {
                     unimplemented!()
                 } else {
                     let callsite = self.new_callsite_label(Some(cur_node));
-                    self.backend.emit_call_near_rel32(callsite, target.name().unwrap())
+                    self.backend.emit_call_near_rel32(callsite, target.name().unwrap(), potentially_excepting)
                 }
             } else if self.match_ireg(func) {
                 let target = self.emit_ireg(func, f_content, f_context, vm);
                 
                 let callsite = self.new_callsite_label(Some(cur_node));
-                self.backend.emit_call_near_r64(callsite, &target)
+                self.backend.emit_call_near_r64(callsite, &target, potentially_excepting)
             } else if self.match_mem(func) {
                 let target = self.emit_mem(func, vm);
                 
                 let callsite = self.new_callsite_label(Some(cur_node));
-                self.backend.emit_call_near_mem64(callsite, &target)
+                self.backend.emit_call_near_mem64(callsite, &target, potentially_excepting)
             } else {
                 unimplemented!()
             }

src/compiler/backend/reg_alloc/graph_coloring/liveness.rs

@@ -271,9 +271,15 @@ fn local_liveness_analysis (cf: &mut CompiledFunction) -> LinkedHashMap<String,
             None => panic!("cannot find range for block {}", block)
         };
 
-        trace!("Block {}: start_inst={}, end_inst(inclusive)={}", block, range.start, range.end-1);
-        start_inst_map.insert(range.start, block);
-        end_inst_map.insert(range.end - 1, block);
+        let first_inst = range.start;
+        let last_inst = match mc.get_last_inst(range.end) {
+            Some(last) => last,
+            None => panic!("cannot find last instruction in block {}, this block contains no instruction?", block)
+        };
+        trace!("Block {}: start_inst={}, end_inst(inclusive)={}", block, first_inst, last_inst);
+
+        start_inst_map.insert(first_inst, block);
+        end_inst_map.insert(last_inst, block);
     }
 
     // local liveness analysis
@@ -324,7 +330,7 @@ fn local_liveness_analysis (cf: &mut CompiledFunction) -> LinkedHashMap<String,
         let succs : Vec<String> = {
             let mut ret = vec![];
 
-            for succ in mc.get_succs(end - 1).into_iter() {
+            for succ in mc.get_succs(mc.get_last_inst(end).unwrap()).into_iter() {
                 match start_inst_map.get(succ) {
                     Some(str) => ret.push(String::from(*str)),
                     None => {}

src/compiler/machine_code.rs

@@ -159,6 +159,9 @@ pub trait MachineCode {
     
     fn get_succs(&self, index: usize) -> &Vec<usize>;
     fn get_preds(&self, index: usize) -> &Vec<usize>;
+
+    fn get_next_inst(&self, index: usize) -> Option<usize>;
+    fn get_last_inst(&self, index: usize) -> Option<usize>;
     
     fn get_inst_reg_uses(&self, index: usize) -> Vec<MuID>;
     fn get_inst_reg_defines(&self, index: usize) -> Vec<MuID>;

tests/ir_macros.rs

@@ -121,6 +121,15 @@ macro_rules! define_block {
             body: vec![$($inst), *],
             keepalives: None
         });
+    };
+
+    (($vm: expr, $fv: ident) $name: ident ($($arg: ident), *) [$exn_arg: ident] {$($inst: ident), *}) => {
+        $name.content = Some(BlockContent{
+            args: vec![$($arg.clone_value()), *],
+            exn_arg: Some($exn_arg.clone_value()),
+            body: vec![$($inst), *],
+            keepalives: None
+        });
     }
 }
 
@@ -383,7 +392,7 @@ macro_rules! inst {
                     }
         });
     };
-    // CALL
+    // CALL (1 return result)
     (($vm: expr, $fv: ident) $name: ident:
         $res: ident = CALL ($($op: ident), *) FUNC($func: expr) ($args: expr) $cc: expr,
                       normal: $norm_dest: ident ($norm_args: expr),
@@ -411,6 +420,35 @@ macro_rules! inst {
             }
         });
     };
+    // CALL (no return value)
+    (($vm: expr, $fv: ident) $name: ident:
+        CALL ($($op: ident), *) FUNC($func: expr) ($args: expr) $cc: expr,
+                      normal: $norm_dest: ident ($norm_args: expr),
+                      exc: $exc_dest: ident ($exc_args: expr)) => {
+        let $name = $fv.new_inst(Instruction {
+            hdr  : MuEntityHeader::unnamed($vm.next_id()),
+            value: None,
+            ops  : RwLock::new(vec![$($op.clone()),*]),
+            v    : Instruction_::Call {
+                data: CallData {
+                    func: $func,
+                    args: $args,
+                    convention: $cc
+                },
+                resume: ResumptionData {
+                    normal_dest: Destination {
+                        target: $norm_dest.id(),
+                        args  : $norm_args
+                    },
+                    exn_dest: Destination {
+                        target: $exc_dest.id(),
+                        args  : $exc_args
+                    }
+                }
+            }
+        });
+    };
+
 
     // RET
     (($vm: expr, $fv: ident) $name: ident: RET ($($val: ident), +)) => {