Native coroutine implementation for ppc64le Linux

* configure.ac: enable fiber coroutine for powerpc64le-linux

* coroutine/ppc64le/Context.S: coroutine_transfer implementation

* coroutine/ppc64le/Context.h: coroutine implementation

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66315 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 54 insertions, 0 deletions

diff --git a/coroutine/ppc64le/Context.h b/coroutine/ppc64le/Context.h
new file mode 100644
index 0000000000..de592f5a46
--- /dev/null
+++ b/coroutine/ppc64le/Context.h
@@ -0,0 +1,54 @@
+#pragma once
+
+#include <assert.h>
+#include <string.h>
+
+#if __cplusplus
+extern "C" {
+#endif
+
+#define COROUTINE __attribute__((noreturn)) void
+
+const size_t COROUTINE_REGISTERS =
+  19  /* 18 general purpose registers (r14-r31) and 1 return address */
+  + 4;  /* space for fiber_entry() to store the link register */
+
+typedef struct
+{
+    void **stack_pointer;
+} coroutine_context;
+
+typedef COROUTINE(* coroutine_start)(coroutine_context *from, coroutine_context *self);
+
+static inline void coroutine_initialize(
+    coroutine_context *context,
+    coroutine_start start,
+    void *stack_pointer,
+    size_t stack_size
+) {
+    /* Force 16-byte alignment */
+    context->stack_pointer = (void**)((uintptr_t)stack_pointer & ~0xF);
+
+    if (!start) {
+        assert(!context->stack_pointer);
+        /* We are main coroutine for this thread */
+        return;
+    }
+
+    context->stack_pointer -= COROUTINE_REGISTERS;
+    memset(context->stack_pointer, 0, sizeof(void*) * COROUTINE_REGISTERS);
+
+    /* Skip a global prologue that sets the TOC register */
+    context->stack_pointer[18] = ((char*)start) + 8;
+}
+
+coroutine_context * coroutine_transfer(coroutine_context * current, coroutine_context * target);
+
+static inline void coroutine_destroy(coroutine_context * context)
+{
+    context->stack_pointer = NULL;
+}
+
+#if __cplusplus
+}
+#endif