[Scummvm-git-logs] scummvm branch-2-7 -> f2e08a5625193ade08fef9d361a4f8346baefd27

[ccawley2011]

This automated email contains information about 2 new commits which have been
pushed to the 'scummvm' repo located at https://github.com/scummvm/scummvm .

Summary:
57fc1f91c8 RISCOS: Use dynamic areas for data and application space for plugins
f2e08a5625 RISCOS: Always use static detection for now


Commit: 57fc1f91c85bac9cb8cab08daf554ad0b36fae35
    https://github.com/scummvm/scummvm/commit/57fc1f91c85bac9cb8cab08daf554ad0b36fae35
Author: Le Philousophe (lephilousophe at users.noreply.github.com)
Date: 2023-02-07T22:16:45Z

Commit Message:
RISCOS: Use dynamic areas for data and application space for plugins

We only use application space in 26-bits (legacy) mode.

Changed paths:
    backends/plugins/riscos/riscos-provider.cpp
    backends/plugins/riscos/riscos-provider.h


diff --git a/backends/plugins/riscos/riscos-provider.cpp b/backends/plugins/riscos/riscos-provider.cpp
index 52446199805..42ecf1cbf2a 100644
--- a/backends/plugins/riscos/riscos-provider.cpp
+++ b/backends/plugins/riscos/riscos-provider.cpp
@@ -32,6 +32,18 @@
 #include <kernel.h>
 #include <swis.h>
 
+// By declaring this variable we force libunixlib to always use dynamic areas for data allocations
+// This frees up space for plugins and allows to have plenty of space for data
+const char *const __dynamic_da_name = "ScummVM Heap";
+
+// HACK: These two function are part of private API in libunixlib
+// They let allocate and free data in the application space where the stack is placed below 64MB
+// When using malloc with big chunks we end up in memory mapped areas above 64MB
+extern "C" {
+extern void *__stackalloc (size_t __size);
+extern void __stackfree (void *__ptr);
+}
+
 // HACK: This is needed so that standard library functions that are only
 // used in plugins can be found in the main executable.
 void pluginHack() {
@@ -75,8 +87,48 @@ protected:
 
 };
 
+/**
+ * On 26-bit RISC OS, plugins need to be allocated in the first 64 MB
+ * of RAM so that it can be executed. This may not be the case when using
+ * the default allocators, which use dynamic areas for large allocations.
+ */
+class RiscOSDLObject_AS : public RiscOSDLObject {
+protected:
+	void *allocateMemory(uint32 align, uint32 size) override {
+		// Allocate with worst case alignment in application space
+		void *p = __stackalloc(size + sizeof(uintptr) + align - 1);
+		void *np = (void *)(((uintptr)p + align - 1) & (-align));
+
+		*(uintptr *)((byte *)np + size) = (uintptr)p;
+
+		debug(8, "Allocated %p while alignment was %d: using %p", p, align, np);
+
+		return np;
+	}
+
+	void deallocateMemory(void *ptr, uint32 size) override {
+		void *p = (void *)*(uintptr *)((byte *)ptr + size);
+		debug(8, "Freeing %p which was allocated at %p", ptr, p);
+		__stackfree(p);
+	}
+};
+
+RiscOSPluginProvider::RiscOSPluginProvider() : _is32bit(false) {
+	__asm__ volatile (
+		"SUBS	%[is32bit], r0, r0\n\t" /* Set at least one status flag and set is32bits to 0 */
+		"TEQ	pc, pc\n\t"				/* First operand never contains flags while second one contains them in 26-bits only */
+		"MOVEQ	%[is32bit], #1\n\t"		/* Set to 1 only if EQ flag is set */
+		: [is32bit] "=r" (_is32bit)
+		: /* no inputs */
+		: "cc");
+}
+
 Plugin *RiscOSPluginProvider::createPlugin(const Common::FSNode &node) const {
-	return new TemplatedELFPlugin<RiscOSDLObject>(node.getPath());
+	if (_is32bit) {
+		return new TemplatedELFPlugin<RiscOSDLObject>(node.getPath());
+	} else {
+		return new TemplatedELFPlugin<RiscOSDLObject_AS>(node.getPath());
+	}
 }
 
 #endif // defined(DYNAMIC_MODULES) && defined(RISCOS)
diff --git a/backends/plugins/riscos/riscos-provider.h b/backends/plugins/riscos/riscos-provider.h
index 171e7e9293f..bcaa6938080 100644
--- a/backends/plugins/riscos/riscos-provider.h
+++ b/backends/plugins/riscos/riscos-provider.h
@@ -28,7 +28,11 @@
 
 class RiscOSPluginProvider : public ELFPluginProvider {
 public:
+	RiscOSPluginProvider();
 	Plugin *createPlugin(const Common::FSNode &node) const;
+
+private:
+	bool _is32bit;
 };
 
 #endif // BACKENDS_PLUGINS_RISCOS_PROVIDER_H


Commit: f2e08a5625193ade08fef9d361a4f8346baefd27
    https://github.com/scummvm/scummvm/commit/f2e08a5625193ade08fef9d361a4f8346baefd27
Author: Cameron Cawley (ccawley2011 at gmail.com)
Date: 2023-02-07T22:16:55Z

Commit Message:
RISCOS: Always use static detection for now

Changed paths:
    configure


diff --git a/configure b/configure
index 65ffbf191f6..31590db87fe 100755
--- a/configure
+++ b/configure
@@ -3191,11 +3191,9 @@ EOF
 		# RiscOS has no OpenGL support at all even though it's SDL based
 		_opengl_mode=none
 		if test "$_dynamic_modules" = yes ; then
-			_detection_features_static=no
 			_plugins_default=dynamic
-		else
-			_detection_features_full=no
 		fi
+		_detection_features_full=no
 		;;
 	solaris*)
 		append_var DEFINES "-DSOLARIS"