Adding upstream version 1.18.10.upstream/1.18.10upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/src/runtime/cgo/gcc_amd64.S b/src/runtime/cgo/gcc_amd64.S
new file mode 100644
index 0000000..46699d1
--- /dev/null
+++ b/src/runtime/cgo/gcc_amd64.S
@@ -0,0 +1,53 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+ * Apple still insists on underscore prefixes for C function names.
+ */
+#if defined(__APPLE__)
+#define EXT(s) _##s
+#else
+#define EXT(s) s
+#endif
+
+/*
+ * void crosscall_amd64(void (*fn)(void), void (*setg_gcc)(void*), void *g)
+ *
+ * Calling into the 6c tool chain, where all registers are caller save.
+ * Called from standard x86-64 ABI, where %rbx, %rbp, %r12-%r15
+ * are callee-save so they must be saved explicitly.
+ * The standard x86-64 ABI passes the three arguments m, g, fn
+ * in %rdi, %rsi, %rdx.
+ */
+.globl EXT(crosscall_amd64)
+EXT(crosscall_amd64):
+	pushq %rbx
+	pushq %rbp
+	pushq %r12
+	pushq %r13
+	pushq %r14
+	pushq %r15
+
+#if defined(_WIN64)
+	movq %r8, %rdi	/* arg of setg_gcc */
+	call *%rdx	/* setg_gcc */
+	call *%rcx	/* fn */
+#else
+	movq %rdi, %rbx
+	movq %rdx, %rdi	/* arg of setg_gcc */
+	call *%rsi	/* setg_gcc */
+	call *%rbx	/* fn */
+#endif
+
+	popq %r15
+	popq %r14
+	popq %r13
+	popq %r12
+	popq %rbp
+	popq %rbx
+	ret
+
+#ifdef __ELF__
+.section .note.GNU-stack,"",@progbits
+#endif