From b558d0996a8a18475f91483d3e3962502422a315 Mon Sep 17 00:00:00 2001
From: hryx <codroid@gmail.com>
Date: Mon, 27 May 2019 19:20:23 -0700
Subject: [PATCH] expr: DeclRefExpr

---
 src-self-hosted/clang.zig       |  2 ++
 src-self-hosted/translate_c.zig | 31 +++++++++++++++++++++++++++++++
 src/zig_clang.cpp               |  5 +++++
 src/zig_clang.h                 |  2 ++
 4 files changed, 40 insertions(+)

diff --git a/src-self-hosted/clang.zig b/src-self-hosted/clang.zig
index ea8f3a6cc6..d1fe5153bb 100644
--- a/src-self-hosted/clang.zig
+++ b/src-self-hosted/clang.zig
@@ -884,3 +884,5 @@ pub extern fn ZigClangImplicitCastExpr_getCastKind(*const ZigClangImplicitCastEx
 pub extern fn ZigClangImplicitCastExpr_getSubExpr(*const ZigClangImplicitCastExpr) *const ZigClangExpr;
 
 pub extern fn ZigClangArrayType_getElementType(*const ZigClangArrayType) ZigClangQualType;
+
+pub extern fn ZigClangDeclRefExpr_getDecl(*const ZigClangDeclRefExpr) *const ZigClangValueDecl;
diff --git a/src-self-hosted/translate_c.zig b/src-self-hosted/translate_c.zig
index 2ccd4eca6d..ffb325d192 100644
--- a/src-self-hosted/translate_c.zig
+++ b/src-self-hosted/translate_c.zig
@@ -107,6 +107,7 @@ const Context = struct {
     decl_table: DeclTable,
     global_scope: *Scope.Root,
     mode: Mode,
+    ptr_params: std.BufSet,
     clang_context: *ZigClangASTContext,
 
     fn a(c: *Context) *std.mem.Allocator {
@@ -184,6 +185,7 @@ pub fn translate(
         .decl_table = DeclTable.init(arena),
         .global_scope = try arena.create(Scope.Root),
         .mode = mode,
+        .ptr_params = std.BufSet.init(arena),
         .clang_context = ZigClangASTUnit_getASTContext(ast_unit).?,
     };
     context.global_scope.* = Scope.Root{
@@ -326,6 +328,7 @@ fn transStmt(
     switch (sc) {
         .CompoundStmtClass => return transCompoundStmt(rp, scope, @ptrCast(*const ZigClangCompoundStmt, stmt)),
         .DeclStmtClass => return transDeclStmt(rp, scope, @ptrCast(*const ZigClangDeclStmt, stmt)),
+        .DeclRefExprClass => return transDeclRefExpr(rp, scope, @ptrCast(*const ZigClangDeclRefExpr, stmt), lrvalue),
         .ImplicitCastExprClass => return transImplicitCastExpr(rp, scope, @ptrCast(*const ZigClangImplicitCastExpr, stmt)),
         else => {
             return revertAndWarn(
@@ -451,6 +454,24 @@ fn transDeclStmt(rp: RestorePoint, parent_scope: *Scope, stmt: *const ZigClangDe
     };
 }
 
+fn transDeclRefExpr(
+    rp: RestorePoint,
+    scope: *Scope,
+    expr: *const ZigClangDeclRefExpr,
+    lrvalue: LRValue,
+) !TransResult {
+    const value_decl = ZigClangDeclRefExpr_getDecl(expr);
+    const c_name = try rp.c.str(ZigClangDecl_getName_bytes_begin(@ptrCast(*const ZigClangDecl, value_decl)));
+    const zig_name = transLookupZigIdentifier(scope, c_name);
+    if (lrvalue == .l_value) try rp.c.ptr_params.put(zig_name);
+    const node = try appendIdentifier(rp.c, zig_name);
+    return TransResult{
+        .node = node,
+        .node_scope = scope,
+        .child_scope = scope,
+    };
+}
+
 fn transImplicitCastExpr(
     rp: RestorePoint,
     scope: *Scope,
@@ -511,6 +532,16 @@ fn findBlockScope(inner: *Scope) *Scope.Block {
     }
 }
 
+fn transLookupZigIdentifier(inner: *Scope, c_name: []const u8) []const u8 {
+    var scope = inner;
+    while (true) : (scope = scope.parent orelse return c_name) {
+        if (scope.id == .Var) {
+            const var_scope = @ptrCast(*const Scope.Var, scope);
+            if (std.mem.eql(u8, var_scope.c_name, c_name)) return var_scope.zig_name;
+        }
+    }
+}
+
 fn maybeSuppressResult(
     rp: RestorePoint,
     scope: *Scope,
diff --git a/src/zig_clang.cpp b/src/zig_clang.cpp
index 2edfda8efa..251c50ae73 100644
--- a/src/zig_clang.cpp
+++ b/src/zig_clang.cpp
@@ -1939,3 +1939,8 @@ struct ZigClangQualType ZigClangArrayType_getElementType(const struct ZigClangAr
     auto casted = reinterpret_cast<const clang::ArrayType *>(self);
     return bitcast(casted->getElementType());
 }
+
+const struct ZigClangValueDecl *ZigClangDeclRefExpr_getDecl(const struct ZigClangDeclRefExpr *self) {
+    auto casted = reinterpret_cast<const clang::DeclRefExpr *>(self);
+    return reinterpret_cast<const struct ZigClangValueDecl *>(casted->getDecl());
+}
diff --git a/src/zig_clang.h b/src/zig_clang.h
index 0afe30c474..086fd7a029 100644
--- a/src/zig_clang.h
+++ b/src/zig_clang.h
@@ -876,4 +876,6 @@ ZIG_EXTERN_C const struct ZigClangExpr *ZigClangImplicitCastExpr_getSubExpr(cons
 
 ZIG_EXTERN_C struct ZigClangQualType ZigClangArrayType_getElementType(const struct ZigClangArrayType *);
 
+ZIG_EXTERN_C const struct ZigClangValueDecl *ZigClangDeclRefExpr_getDecl(const struct ZigClangDeclRefExpr *);
+
 #endif