Minor optimization, removing do/while(0) patterns in some cases as they translate to runtime

(e.g. translate to xor + test + jne in VS x84, unnecessary)

imgui_draw.cpp

@@ -705,10 +705,11 @@ void ImDrawList::PrimQuadUV(const ImVec2& a, const ImVec2& b, const ImVec2& c, c
 }
 
 // On AddPolyline() and AddConvexPolyFilled() we intentionally avoid using ImVec2 and superfluous function calls to optimize debug/non-inlined builds.
-// Those macros expects l-values.
+// - Those macros expects l-values and need to be used as their own statement.
-#define IM_NORMALIZE2F_OVER_ZERO(VX,VY)     do { float d2 = VX*VX + VY*VY; if (d2 > 0.0f) { float inv_len = ImRsqrt(d2); VX *= inv_len; VY *= inv_len; } } while (0)
+// - Those macros are intentionally not surrounded by the 'do {} while (0)' idiom because even that translates to runtime with debug compilers.
+#define IM_NORMALIZE2F_OVER_ZERO(VX,VY)     { float d2 = VX*VX + VY*VY; if (d2 > 0.0f) { float inv_len = ImRsqrt(d2); VX *= inv_len; VY *= inv_len; } } (void)0
 #define IM_FIXNORMAL2F_MAX_INVLEN2          100.0f // 500.0f (see #4053, #3366)
-#define IM_FIXNORMAL2F(VX,VY)               do { float d2 = VX*VX + VY*VY; if (d2 > 0.000001f) { float inv_len2 = 1.0f / d2; if (inv_len2 > IM_FIXNORMAL2F_MAX_INVLEN2) inv_len2 = IM_FIXNORMAL2F_MAX_INVLEN2; VX *= inv_len2; VY *= inv_len2; } } while (0)
+#define IM_FIXNORMAL2F(VX,VY)               { float d2 = VX*VX + VY*VY; if (d2 > 0.000001f) { float inv_len2 = 1.0f / d2; if (inv_len2 > IM_FIXNORMAL2F_MAX_INVLEN2) inv_len2 = IM_FIXNORMAL2F_MAX_INVLEN2; VX *= inv_len2; VY *= inv_len2; } } (void)0
 
 // TODO: Thickness anti-aliased lines cap are missing their AA fringe.
 // We avoid using the ImVec2 math operators here to reduce cost to a minimum for debug/non-inlined builds.

imgui_internal.h

@@ -2709,11 +2709,7 @@ extern void         ImGuiTestEngineHook_Log(ImGuiContext* ctx, const char* fmt,
 #define IMGUI_TEST_ENGINE_ID_INFO(_ID,_TYPE,_DATA)          if (g.TestEngineHookIdInfo == id) ImGuiTestEngineHook_IdInfo(&g, _TYPE, _ID, (const void*)(_DATA));
 #define IMGUI_TEST_ENGINE_ID_INFO2(_ID,_TYPE,_DATA,_DATA2)  if (g.TestEngineHookIdInfo == id) ImGuiTestEngineHook_IdInfo(&g, _TYPE, _ID, (const void*)(_DATA), (const void*)(_DATA2));
 #else
-#define IMGUI_TEST_ENGINE_ITEM_ADD(_BB,_ID)                 do { } while (0)
+#define IMGUI_TEST_ENGINE_ITEM_INFO(_ID,_LABEL,_FLAGS)      ((void)0)
-#define IMGUI_TEST_ENGINE_ITEM_INFO(_ID,_LABEL,_FLAGS)      do { } while (0)
-#define IMGUI_TEST_ENGINE_LOG(_FMT,...)                     do { } while (0)
-#define IMGUI_TEST_ENGINE_ID_INFO(_ID,_TYPE,_DATA)          do { } while (0)
-#define IMGUI_TEST_ENGINE_ID_INFO2(_ID,_TYPE,_DATA,_DATA2)  do { } while (0)
 #endif
 
 //-----------------------------------------------------------------------------