From 30d1e1d6c99f37d2d5c61d4f82e651124896b81b Mon Sep 17 00:00:00 2001
From: water111 <48171810+water111@users.noreply.github.com>
Date: Sat, 21 Aug 2021 10:20:55 -0400
Subject: [PATCH] [decompiler] maybe fix symbol decompile issue (#776)

* maybe fix symbol decompile issue

* try again on a label

* allow int to float on seconds
---
 decompiler/IR2/AtomicOpForm.cpp                  | 16 ++++++++++++++++
 decompiler/IR2/FormExpressionAnalysis.cpp        |  2 +-
 decompiler/util/data_decompile.cpp               | 15 +++++++++------
 .../decompiler/reference/engine/ps2/timer_REF.gc |  2 +-
 4 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/decompiler/IR2/AtomicOpForm.cpp b/decompiler/IR2/AtomicOpForm.cpp
index 48a402346c..d7d1fbb80b 100644
--- a/decompiler/IR2/AtomicOpForm.cpp
+++ b/decompiler/IR2/AtomicOpForm.cpp
@@ -549,6 +549,22 @@ FormElement* make_label_load(int label_idx,
     }
   }
 
+  if (load_kind != LoadVarOp::Kind::FLOAT && load_size == 8) {
+    if ((int)env.file->words_by_seg.at(label.target_segment).size() > (label.offset / 4) + 1) {
+      assert((label.offset % 8) == 0);
+      auto word0 = env.file->words_by_seg.at(label.target_segment).at(label.offset / 4);
+      auto word1 = env.file->words_by_seg.at(label.target_segment).at(1 + (label.offset / 4));
+      assert(word0.kind == LinkedWord::PLAIN_DATA);
+      assert(word1.kind == LinkedWord::PLAIN_DATA);
+      u64 value;
+      memcpy(&value, &word0.data, 4);
+      memcpy(((u8*)&value) + 4, &word1.data, 4);
+      return pool.alloc_element<CastElement>(TypeSpec("uint"),
+                                             pool.alloc_single_element_form<SimpleAtomElement>(
+                                                 nullptr, SimpleAtom::make_int_constant(value)));
+    }
+  }
+
   return nullptr;
 }
 
diff --git a/decompiler/IR2/FormExpressionAnalysis.cpp b/decompiler/IR2/FormExpressionAnalysis.cpp
index c76c1ef0a0..ad92abebc2 100644
--- a/decompiler/IR2/FormExpressionAnalysis.cpp
+++ b/decompiler/IR2/FormExpressionAnalysis.cpp
@@ -1800,7 +1800,7 @@ void SimpleExpressionElement::update_from_stack_int_to_float(const Env& env,
   auto fpr_convert_matcher =
       Matcher::op(GenericOpMatcher::fixed(FixedOperatorKind::GPR_TO_FPR), {Matcher::any(0)});
   auto type = env.get_types_before_op(var.idx()).get(var.reg()).typespec();
-  if (type == TypeSpec("int") || type == TypeSpec("uint")) {
+  if (type == TypeSpec("int") || type == TypeSpec("uint") || type == TypeSpec("seconds")) {
     auto mr = match(fpr_convert_matcher, arg);
     if (mr.matched) {
       arg = mr.maps.forms.at(0);
diff --git a/decompiler/util/data_decompile.cpp b/decompiler/util/data_decompile.cpp
index 21ac31535c..e405658e92 100644
--- a/decompiler/util/data_decompile.cpp
+++ b/decompiler/util/data_decompile.cpp
@@ -588,12 +588,6 @@ goos::Object decompile_structure(const TypeSpec& type,
       continue;
     }
 
-    // OK - READ THE FIELD:
-    for (int i = field_start; i < field_end; i++) {
-      // even if our field was partially zero, we mark those zero bytes as "has data".
-      field_status_per_byte.at(i) = HAS_DATA_READ;
-    }
-
     // first, let's see if it's a value or reference
     auto field_type_info = ts.lookup_type(field.type());
     if (!field_type_info->is_reference()) {
@@ -627,6 +621,9 @@ goos::Object decompile_structure(const TypeSpec& type,
               field.name(), sp_field_init_spec_decompile(obj_words, labels, label.target_segment,
                                                          field_start, ts, field, words, file));
         } else {
+          if (obj_words.at(field_start / 4).kind != LinkedWord::PLAIN_DATA) {
+            continue;
+          }
           std::vector<u8> bytes_out;
           for (int byte_idx = field_start; byte_idx < field_end; byte_idx++) {
             bytes_out.push_back(obj_words.at(byte_idx / 4).get_byte(byte_idx % 4));
@@ -758,6 +755,12 @@ goos::Object decompile_structure(const TypeSpec& type,
         }
       }
     }
+
+    // OK - READ THE FIELD:
+    for (int i = field_start; i < field_end; i++) {
+      // even if our field was partially zero, we mark those zero bytes as "has data".
+      field_status_per_byte.at(i) = HAS_DATA_READ;
+    }
   }
 
   for (size_t i = 0; i < field_status_per_byte.size(); i++) {
diff --git a/test/decompiler/reference/engine/ps2/timer_REF.gc b/test/decompiler/reference/engine/ps2/timer_REF.gc
index 542c9f4019..b13183bf60 100644
--- a/test/decompiler/reference/engine/ps2/timer_REF.gc
+++ b/test/decompiler/reference/engine/ps2/timer_REF.gc
@@ -31,7 +31,7 @@
 ;; WARN: Unsupported inline assembly instruction kind - [sync.p]
 (defun disable-irq ()
   (local-vars (v0-0 int))
-  (let ((v1-0 (l.d L21)))
+  (let ((v1-0 (the-as uint #xfffffffe)))
    (.mfc0 v0-0 Status)
    (let ((v0-1 (logand v0-0 v1-0)))
     (.mtc0 Status v0-1)