runtime: move loong64 library entry point to os-agnostic file

The library entry point for loong64 is agnostic to the OS, so move it to
asm_loong64.s. This is similar to what we do for other architectures.

Cq-Include-Trybots: luci.golang.try:gotip-linux-loong64
Change-Id: I6915eb76d3ea72a779e05e78d85f24793169c61f
Reviewed-on: https://go-review.googlesource.com/c/go/+/706416
Reviewed-by: abner chenc <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>
Reviewed-by: Keith Randall <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: qmuntal

src/runtime/asm_loong64.s

@@ -6,6 +6,57 @@
 #include "go_tls.h"
 #include "funcdata.h"
 #include "textflag.h"
+#include "cgo/abi_loong64.h"
+
+// When building with -buildmode=c-shared, this symbol is called when the shared
+// library is loaded.
+TEXT _rt0_loong64_lib(SB),NOSPLIT,$168
+	// Preserve callee-save registers.
+	SAVE_R22_TO_R31(3*8)
+	SAVE_F24_TO_F31(13*8)
+
+	// Initialize g as nil in case of using g later e.g. sigaction in cgo_sigaction.go
+	MOVV	R0, g
+
+	MOVV	R4, _rt0_loong64_lib_argc<>(SB)
+	MOVV	R5, _rt0_loong64_lib_argv<>(SB)
+
+	// Synchronous initialization.
+	MOVV	$runtime·libpreinit(SB), R19
+	JAL	(R19)
+
+	// Create a new thread to do the runtime initialization and return.
+	MOVV	_cgo_sys_thread_create(SB), R19
+	BEQ	R19, nocgo
+	MOVV	$_rt0_loong64_lib_go(SB), R4
+	MOVV	$0, R5
+	JAL	(R19)
+	JMP	restore
+
+nocgo:
+	MOVV	$0x800000, R4                     // stacksize = 8192KB
+	MOVV	$_rt0_loong64_lib_go(SB), R5
+	MOVV	R4, 8(R3)
+	MOVV	R5, 16(R3)
+	MOVV	$runtime·newosproc0(SB), R19
+	JAL	(R19)
+
+restore:
+	// Restore callee-save registers.
+	RESTORE_R22_TO_R31(3*8)
+	RESTORE_F24_TO_F31(13*8)
+	RET
+
+TEXT _rt0_loong64_lib_go(SB),NOSPLIT,$0
+	MOVV	_rt0_loong64_lib_argc<>(SB), R4
+	MOVV	_rt0_loong64_lib_argv<>(SB), R5
+	MOVV	$runtime·rt0_go(SB),R19
+	JMP	(R19)
+
+DATA _rt0_loong64_lib_argc<>(SB)/8, $0
+GLOBL _rt0_loong64_lib_argc<>(SB),NOPTR, $8
+DATA _rt0_loong64_lib_argv<>(SB)/8, $0
+GLOBL _rt0_loong64_lib_argv<>(SB),NOPTR, $8
 
 #define	REGCTXT	R29
 

src/runtime/rt0_linux_loong64.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 #include "textflag.h"
-#include "cgo/abi_loong64.h"
 
 TEXT _rt0_loong64_linux(SB),NOSPLIT|NOFRAME,$0
 	// In a statically linked binary, the stack contains argc,
@@ -16,53 +15,8 @@ TEXT _rt0_loong64_linux(SB),NOSPLIT|NOFRAME,$0
 
 // When building with -buildmode=c-shared, this symbol is called when the shared
 // library is loaded.
-TEXT _rt0_loong64_linux_lib(SB),NOSPLIT,$168
-	// Preserve callee-save registers.
-	SAVE_R22_TO_R31(3*8)
-	SAVE_F24_TO_F31(13*8)
-
-	// Initialize g as nil in case of using g later e.g. sigaction in cgo_sigaction.go
-	MOVV	R0, g
-
-	MOVV	R4, _rt0_loong64_linux_lib_argc<>(SB)
-	MOVV	R5, _rt0_loong64_linux_lib_argv<>(SB)
-
-	// Synchronous initialization.
-	MOVV	$runtime·libpreinit(SB), R19
-	JAL	(R19)
-
-	// Create a new thread to do the runtime initialization and return.
-	MOVV	_cgo_sys_thread_create(SB), R19
-	BEQ	R19, nocgo
-	MOVV	$_rt0_loong64_linux_lib_go(SB), R4
-	MOVV	$0, R5
-	JAL	(R19)
-	JMP	restore
-
-nocgo:
-	MOVV	$0x800000, R4                     // stacksize = 8192KB
-	MOVV	$_rt0_loong64_linux_lib_go(SB), R5
-	MOVV	R4, 8(R3)
-	MOVV	R5, 16(R3)
-	MOVV	$runtime·newosproc0(SB), R19
-	JAL	(R19)
-
-restore:
-	// Restore callee-save registers.
-	RESTORE_R22_TO_R31(3*8)
-	RESTORE_F24_TO_F31(13*8)
-	RET
-
-TEXT _rt0_loong64_linux_lib_go(SB),NOSPLIT,$0
-	MOVV	_rt0_loong64_linux_lib_argc<>(SB), R4
-	MOVV	_rt0_loong64_linux_lib_argv<>(SB), R5
-	MOVV	$runtime·rt0_go(SB),R19
-	JMP	(R19)
-
-DATA _rt0_loong64_linux_lib_argc<>(SB)/8, $0
-GLOBL _rt0_loong64_linux_lib_argc<>(SB),NOPTR, $8
-DATA _rt0_loong64_linux_lib_argv<>(SB)/8, $0
-GLOBL _rt0_loong64_linux_lib_argv<>(SB),NOPTR, $8
+TEXT _rt0_loong64_linux_lib(SB),NOSPLIT,$0
+	JMP	_rt0_loong64_lib(SB)
 
 TEXT main(SB),NOSPLIT|NOFRAME,$0
 	// in external linking, glibc jumps to main with argc in R4