feat(verify): add Call trampolines for arm64, riscv64, loong64

Assisted-by: MiMo V2.5 Pro

verify/trampoline_riscv64.s

@@ -0,0 +1,31 @@
+// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include "textflag.h"
+
+// ABI0 JIT trampoline for RISC-V 64.
+//
+// enterJIT saves Go SP and RA, switches to the prepared stack, and jumps
+// to the JIT function.  When the function RETs (JALR zero, ra, 0), control
+// lands in leaveJIT.
+
+// func enterJIT(fn uintptr, stack uintptr)
+TEXT ·enterJIT(SB), NOSPLIT, $0-16
+	MOV  fn+0(FP), X5          // target function address (T0)
+	MOV  X1, savedRA(SB)       // save return address
+	MOV  X2, savedSP(SB)       // save Go stack pointer
+	MOV  stack+8(FP), X6       // load prepared stack pointer (T1)
+	LD   0(X6), X1             // load leaveJIT address into RA
+	ADD  $8, X6, X6            // advance past return address
+	MOV  X6, X2                // switch to prepared stack (SP)
+	JALR X0, 0(X5)             // jump to JIT function
+
+// func leaveJIT()
+TEXT ·leaveJIT(SB), NOSPLIT, $0-0
+	MOV  savedSP(SB), X6       // restore Go stack pointer
+	MOV  X6, X2                // restore SP
+	MOV  savedRA(SB), X1       // restore return address
+	JALR X0, 0(X1)             // return to Go caller
+
+GLOBL savedRA(SB), NOPTR, $8
+GLOBL savedSP(SB), NOPTR, $8