Commit ec17f4ebbef624526ed68f4fffcb2c5eec71bef9 | zig

author	Andrew Kelley <andrew@ziglang.org> 2019-06-07 14:20:35-04:00
committer	Andrew Kelley <andrew@ziglang.org> 2019-06-07 14:20:35-04:00
log	ec17f4ebbef624526ed68f4fffcb2c5eec71bef9
tree	23f2670f3d0fc05792f04fa952952aa6746bd3a5
parent	4c222a482fa3807fce8455aa54fe4931bee7bb37
signature	Commit is signed but in an unrecognized format.

fix behavior for peer result locs with one prong unreachable

3 files changed, 21 insertions(+), 10 deletions(-)

BRANCH_TODO
src
- all_types.hpp
- ir.cpp

BRANCH_TODO-5

...	@@ -33,9 +33,4 @@ handle if with no else	...	@@ -33,9 +33,4 @@ handle if with no else
33		33
34		34
35		35
36	static IrInstruction ir_const_unreachable(IrAnalyze ira, IrInstruction *source_instruction) {
37	IrInstruction *result = ir_const(ira, source_instruction, ira->codegen->builtin_types.entry_unreachable);
38	result->value.special = ConstValSpecialStatic;
39	return result;
40	}
41		36

src/all_types.hpp+1

...	@@ -3628,6 +3628,7 @@ struct IrSuspendPosition {	...	@@ -3628,6 +3628,7 @@ struct IrSuspendPosition {
3628	struct ResultLocPeer {	3628	struct ResultLocPeer {
3629	ResultLoc base;	3629	ResultLoc base;
3630		3630
		3631	bool seen_before;
3631	ResultLocPeerParent *parent;	3632	ResultLocPeerParent *parent;
3632	IrBasicBlock *next_bb;	3633	IrBasicBlock *next_bb;
3633	IrSuspendPosition suspend_pos;	3634	IrSuspendPosition suspend_pos;

src/ir.cpp+20-5

 @@ -10659,6 +10659,12 @@ static IrInstruction *ir_const_undef(IrAnalyze *ira, IrInstruction *source_instr
     return result;
 }
+static IrInstruction *ir_const_unreachable(IrAnalyze *ira, IrInstruction *source_instruction) {
+    IrInstruction *result = ir_const(ira, source_instruction, ira->codegen->builtin_types.entry_unreachable);
+    result->value.special = ConstValSpecialStatic;
+    return result;
+}
 static IrInstruction *ir_const_void(IrAnalyze *ira, IrInstruction *source_instruction) {
     return ir_const(ira, source_instruction, ira->codegen->builtin_types.entry_void);
 }
 @@ -14461,7 +14467,9 @@ static IrInstruction *ir_resolve_result(IrAnalyze *ira, IrInstruction *suspend_s
             if (peer_parent->resolved_type == nullptr) {
                 IrInstruction *suspended_inst = ira_suspend(ira, suspend_source_instr,
                         result_peer->next_bb, &result_peer->suspend_pos);
-                bool last_one = (result_peer == &peer_parent->peers[peer_parent->peer_count - 1]);
+                bool last_one = result_peer->seen_before ||
+                    result_peer == &peer_parent->peers[peer_parent->peer_count - 1];
+                result_peer->seen_before = true;
                 if (!last_one) {
                     return suspended_inst;
                 }
 @@ -14472,13 +14480,20 @@ static IrInstruction *ir_resolve_result(IrAnalyze *ira, IrInstruction *suspend_s
                     IrInstruction *gen_instruction = this_peer->base.gen_instruction;
                     if (gen_instruction == nullptr) {
-                        instructions[i] = ir_const(ira, this_peer->base.source_instruction,
+                        // unreachable instructions will cause implicit_elem_type to be null
-                                this_peer->base.implicit_elem_type);
+                        if (this_peer->base.implicit_elem_type == nullptr) {
-                        instructions[i]->value.special = ConstValSpecialRuntime;
+                            instructions[i] = ir_const_unreachable(ira, this_peer->base.source_instruction);
+                        } else {
+                            instructions[i] = ir_const(ira, this_peer->base.source_instruction,
+                                    this_peer->base.implicit_elem_type);
+                            instructions[i]->value.special = ConstValSpecialRuntime;
+                        }
                     } else {
                         instructions[i] = gen_instruction;
                     }
-                    if (opposite_peer->base.implicit_elem_type->id != ZigTypeIdUnreachable) {
+                    if (opposite_peer->base.implicit_elem_type != nullptr &&
+                        opposite_peer->base.implicit_elem_type->id != ZigTypeIdUnreachable)
+                    {
                         ira->resume_stack.append(opposite_peer->suspend_pos);
                     }
                 }