Add test for PolkaVM linker debug-info parse error

Cargo.toml

@@ -49,6 +49,7 @@ which = "8.0"
 path-slash = "0.2"
 rayon = "1.11"
 clap = { version = "4", default-features = false, features = ["derive"] }
+# TODO: Bump polkavm-* when a new release containing commit `ffddfe4` exists.
 polkavm-common = "0.35.0"
 polkavm-linker = "0.35.0"
 polkavm-disassembler = "0.35.0"

crates/resolc/src/test_utils.rs

@@ -56,6 +56,8 @@ struct CachedBlob {
 }
 
 /// Builds the Solidity project and returns the standard JSON output.
+/// [`OptimizerSettings::cycles`] will be used. Debug info is emitted
+/// at every optimization level except `-Oz`.
 pub fn build_solidity(
     sources: BTreeMap<String, SolcStandardJsonInputSource>,
 ) -> anyhow::Result<SolcStandardJsonOutput> {
@@ -70,6 +72,7 @@ pub fn build_solidity(
 }
 
 /// Builds the Solidity project and returns the standard JSON output.
+/// Debug info is emitted at every optimization level except `-Oz`.
 pub fn build_solidity_with_options(
     sources: BTreeMap<String, SolcStandardJsonInputSource>,
     libraries: SolcStandardJsonInputSettingsLibraries,

crates/resolc/src/tests/unit/debug_info.rs

@@ -0,0 +1,61 @@
+//! The Solidity compiler tests for debug info.
+
+use revive_llvm_context::OptimizerSettings;
+
+use crate::test_utils::{build_solidity_with_options, sources};
+
+/// Test for a PolkaVM debug line-program with too many instructions.
+///
+/// At `-O1` through `-O3` and `-Os`, LLVM merges the identical code of many repeated
+/// calls. With debug info enabled the merged instruction is attributed to every
+/// original call site at once, so the PolkaVM linker reconstructs a very deep
+/// inline-frame stack for a single instruction. A debug `resolc` build invoked with `-g`
+/// panicked when there were more line-program ops than the runtime parser read per region.
+#[test]
+fn many_repeated_calls_do_not_overflow_the_line_program() {
+    let code = r#"
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.0;
+interface I {
+    function f(uint256) external;
+}
+contract Test {
+    function run(I t, uint256 acc) external {
+        t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc);
+        t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc);
+        t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc);
+        t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc); t.f(acc);
+    }
+}
+"#;
+
+    for opt_level in ['1', '2', '3', 's'] {
+        let output = build_solidity_with_options(
+            sources(&[("test.sol", code)]),
+            Default::default(),
+            Default::default(),
+            OptimizerSettings::try_from_cli(opt_level).unwrap(),
+            true,
+            Default::default(),
+        )
+        .unwrap_or_else(|error| panic!("-O{opt_level} should compile: {error}"));
+
+        assert!(
+            !output
+                .contracts
+                .get("test.sol")
+                .expect("`test.sol` should exist")
+                .get("Test")
+                .expect("contract `Test` should exist")
+                .evm
+                .as_ref()
+                .expect("`evm` field should exist")
+                .bytecode
+                .as_ref()
+                .expect("`bytecode` field should exist")
+                .object
+                .is_empty(),
+            "-O{opt_level} should generate bytecode"
+        );
+    }
+}

crates/resolc/src/tests/unit/mod.rs

@@ -1,5 +1,6 @@
 //! The Solidity compiler unit tests.
 
+mod debug_info;
 mod factory_dependency;
 mod ir_artifacts;
 mod libraries;