diff options
| -rw-r--r-- | tvix/eval/src/compiler/mod.rs | 26 | ||||
| -rw-r--r-- | tvix/eval/src/opcode.rs | 4 | ||||
| -rw-r--r-- | tvix/eval/src/vm.rs | 6 |
3 files changed, 26 insertions, 10 deletions
diff --git a/tvix/eval/src/compiler/mod.rs b/tvix/eval/src/compiler/mod.rs index 1463bb100eae..941b945a8bb6 100644 --- a/tvix/eval/src/compiler/mod.rs +++ b/tvix/eval/src/compiler/mod.rs @@ -630,16 +630,34 @@ impl Compiler<'_> { self.patch_jump(final_jump); } + /// Compile `assert` expressions using jumping instructions in the VM. + /// + /// ```notrust + /// ┌─────────────────────┐ + /// │ 0 [ conditional ] │ + /// │ 1 JUMP_IF_FALSE →┼─┐ + /// │ 2 [ main body ] │ │ Jump to else body if + /// ┌┼─3─← JUMP │ │ condition is false. + /// Jump over else body ││ 4 OP_ASSERT_FAIL ←┼─┘ + /// if condition is true.└┼─5─→ ... │ + /// └─────────────────────┘ + /// ``` fn compile_assert(&mut self, slot: LocalIdx, node: &ast::Assert) { // Compile the assertion condition to leave its value on the stack. self.compile(slot, &node.condition().unwrap()); self.emit_force(&node.condition().unwrap()); - self.push_op(OpCode::OpAssert, &node.condition().unwrap()); + let then_idx = self.push_op(OpCode::OpJumpIfFalse(JumpOffset(0)), node); - // The runtime will abort evaluation at this point if the - // assertion failed, if not the body simply continues on like - // normal. + self.push_op(OpCode::OpPop, node); self.compile(slot, &node.body().unwrap()); + + let else_idx = self.push_op(OpCode::OpJump(JumpOffset(0)), node); + + self.patch_jump(then_idx); + self.push_op(OpCode::OpPop, node); + self.push_op(OpCode::OpAssertFail, &node.condition().unwrap()); + + self.patch_jump(else_idx); } /// Compile conditional expressions using jumping instructions in the VM. diff --git a/tvix/eval/src/opcode.rs b/tvix/eval/src/opcode.rs index c2eabba1c28e..15f60a538c41 100644 --- a/tvix/eval/src/opcode.rs +++ b/tvix/eval/src/opcode.rs @@ -121,8 +121,8 @@ pub enum OpCode { /// Close scopes while leaving their expression value around. OpCloseScope(Count), // number of locals to pop - /// Asserts stack top is a boolean, and true. - OpAssert, + /// Return an error indicating that an `assert` failed + OpAssertFail, // Lambdas & closures OpCall, diff --git a/tvix/eval/src/vm.rs b/tvix/eval/src/vm.rs index b89b61f7626a..01299ccc17da 100644 --- a/tvix/eval/src/vm.rs +++ b/tvix/eval/src/vm.rs @@ -561,10 +561,8 @@ impl<'o> VM<'o> { } } - OpCode::OpAssert => { - if !fallible!(self, self.pop().as_bool()) { - return Err(self.error(ErrorKind::AssertionFailed)); - } + OpCode::OpAssertFail => { + return Err(self.error(ErrorKind::AssertionFailed)); } OpCode::OpCall => { |