From cc401c1e5ba3a2286a77e846e8112410471c542f Mon Sep 17 00:00:00 2001
From: Janeczko Jakub <105227351+qbojj@users.noreply.github.com>
Date: Wed, 31 Jan 2024 12:19:24 +0100
Subject: [PATCH] fix string type sso computation (#469)

* fix string type sso computation

* fix rest of sbo/sso calculation

* make placement of uintptr_t cast consistent

* separate check-inline into function
---
 oi/OITraceCode.cpp           |  6 ++++--
 types/cxx11_string_type.toml |  9 ++-------
 types/fb_string_type.toml    |  4 +---
 types/small_vec_type.toml    | 11 +++--------
 types/string_type.toml       |  9 ++-------
 5 files changed, 12 insertions(+), 27 deletions(-)

diff --git a/oi/OITraceCode.cpp b/oi/OITraceCode.cpp
index 362ce69..af99753 100644
--- a/oi/OITraceCode.cpp
+++ b/oi/OITraceCode.cpp
@@ -185,8 +185,10 @@ struct validate_offset {
 enum class StubbedPointer : uintptr_t {};
 
 bool isStorageInline(const auto& c) {
-  return (uintptr_t)std::data(c) < (uintptr_t)(&c + sizeof(c)) &&
-         (uintptr_t)std::data(c) >= (uintptr_t)&c;
+  uintptr_t data_p = (uintptr_t)std::data(c);
+  uintptr_t container_p = (uintptr_t)&c;
+
+  return data_p >= container_p && data_p < container_p + sizeof(c);
 }
 
 namespace {
diff --git a/types/cxx11_string_type.toml b/types/cxx11_string_type.toml
index c88debd..fbf4788 100644
--- a/types/cxx11_string_type.toml
+++ b/types/cxx11_string_type.toml
@@ -28,10 +28,7 @@ void getSizeType(const %1%<T, Traits, Allocator> &container, size_t& returnArg)
     // Test for small string optimisation - whether the underlying string is
     // contained within the string object.
     SAVE_SIZE(
-      (((uintptr_t)container.data() < (uintptr_t)(&container + sizeof(%1%<T>)))
-        &&
-      ((uintptr_t)container.data() >= (uintptr_t)&container))
-        ? 0 : (container.capacity() * sizeof(T))
+      isStorageInline(container) ? 0 : (container.capacity() * sizeof(T))
     );
 }
 """
@@ -55,9 +52,7 @@ class CaptureKeyHandler<Ctx, std::__cxx11::basic_string<CharT, Traits, Allocator
 """
 
 traversal_func = """
-    bool sso = ((uintptr_t)container.data() <
-                (uintptr_t)(&container + sizeof(std::__cxx11::basic_string<T0>))) &&
-               ((uintptr_t)container.data() >= (uintptr_t)&container);
+    bool sso = isStorageInline(container);
 
     return returnArg.write(container.capacity())
         .write(sso)
diff --git a/types/fb_string_type.toml b/types/fb_string_type.toml
index 169be87..c5c9ef5 100644
--- a/types/fb_string_type.toml
+++ b/types/fb_string_type.toml
@@ -25,9 +25,7 @@ void getSizeType(const %1%<E, T, A, Storage> &container, size_t& returnArg)
     SAVE_DATA((uintptr_t)container.capacity());
     SAVE_DATA((uintptr_t)container.size());
 
-    bool inlined = ((uintptr_t)container.data() < (uintptr_t)(&container + sizeof(%1%<E, T, A, Storage>)))
-        &&
-      ((uintptr_t)container.data() >= (uintptr_t)&container);
+    bool inlined = isStorageInline(container);
 
     if (!inlined && ctx.pointers.add((uintptr_t)container.data())) {
       SAVE_SIZE(container.capacity() * sizeof(T));
diff --git a/types/small_vec_type.toml b/types/small_vec_type.toml
index a5f1694..9f39677 100644
--- a/types/small_vec_type.toml
+++ b/types/small_vec_type.toml
@@ -22,8 +22,8 @@ void getSizeType(const %1%<V, N, P> &container, size_t& returnArg)
 {
     SAVE_SIZE(sizeof(%1%<V, N, P>));
 
-    bool dataInlined = ((uintptr_t)container.data() >= (uintptr_t)&container) &&
-                       ((uintptr_t)container.data() < (uintptr_t)(&container + sizeof(%1%<V, N, P>)));
+    bool dataInlined = isStorageInline(container);
+
     if (dataInlined) {
       // Don't double count inlined elements
       SAVE_SIZE(-(container.size() * sizeof(V)));
@@ -43,12 +43,7 @@ void getSizeType(const %1%<V, N, P> &container, size_t& returnArg)
 """
 
 traversal_func = """
-// If `container.data()` pointer is within the container struct,
-// then the container's storage is inlined and doesn't uses the heap.
-// TODO: Is there an API to get this information?
-bool uses_intern_storage =
-  (uintptr_t)&container <= (uintptr_t)container.data() &&
-  (uintptr_t)container.data() < ((uintptr_t)&container + sizeof(container));
+bool uses_intern_storage = isStorageInline(container);
 
 auto tail = returnArg
   .write((uintptr_t)uses_intern_storage)
diff --git a/types/string_type.toml b/types/string_type.toml
index 0d2ab0d..c221da6 100644
--- a/types/string_type.toml
+++ b/types/string_type.toml
@@ -28,18 +28,13 @@ void getSizeType(const %1%<T, Traits, Allocator> &container, size_t& returnArg)
     // Test for small string optimisation - whether the underlying string is
     // contained within the string object.
     SAVE_SIZE(
-      ((uintptr_t)container.data() < (uintptr_t)(&container + sizeof(%1%<T>)))
-        &&
-      ((uintptr_t)container.data() >= (uintptr_t)&container)
-        ? 0 : (container.capacity() * sizeof(T))
+      isStorageInline(container) ? 0 : (container.capacity() * sizeof(T))
     );
 }
 """
 
 traversal_func = """
-    bool sso = ((uintptr_t)container.data() <
-                (uintptr_t)(&container + sizeof(std::__cxx11::basic_string<T0>))) &&
-               ((uintptr_t)container.data() >= (uintptr_t)&container);
+    bool sso = isStorageInline(container);
 
     return returnArg.write(container.capacity())
         .write(sso)