1 files changed, 57 insertions, 0 deletions
diff --git a/coroutine/ppc64/Context.h b/coroutine/ppc64/Context.h
new file mode 100644
index 0000000000..085b475ed5
--- /dev/null
+++ b/coroutine/ppc64/Context.h
@@ -0,0 +1,57 @@
+#ifndef COROUTINE_PPC64_CONTEXT_H
+#define COROUTINE_PPC64_CONTEXT_H 1
+
+#pragma once
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#define COROUTINE __attribute__((noreturn)) void
+
+enum {
+  COROUTINE_REGISTERS =
+  20  /* 19 general purpose registers (r13-r31) and 1 return address */
+  + 4  /* space for fiber_entry() to store the link register */
+};
+
+struct coroutine_context
+{
+    void **stack_pointer;
+    void *argument;
+};
+
+typedef COROUTINE(* coroutine_start)(struct coroutine_context *from, struct coroutine_context *self);
+
+static inline void coroutine_initialize_main(struct coroutine_context * context) {
+    context->stack_pointer = NULL;
+}
+
+static inline void coroutine_initialize(
+    struct coroutine_context *context,
+    coroutine_start start,
+    void *stack,
+    size_t size
+) {
+    assert(start && stack && size >= 1024);
+
+    // Stack grows down. Force 16-byte alignment.
+    char * top = (char*)stack + size;
+    context->stack_pointer = (void**)((uintptr_t)top & ~0xF);
+
+    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[19] = ((char*)start) + 8;
+}
+
+struct coroutine_context * coroutine_transfer(struct coroutine_context * current, struct coroutine_context * target);
+
+static inline void coroutine_destroy(struct coroutine_context * context)
+{
+    context->stack_pointer = NULL;
+}
+
+#endif /* COROUTINE_PPC64_CONTEXT_H */