Add memory operation syscalls (backport #16447) (#18149)

* Add memory operation syscalls (#16447)

(cherry picked from commit 2b50529265)

# Conflicts:
#	programs/bpf/Cargo.lock
#	programs/bpf/rust/sysvar/tests/lib.rs
#	programs/bpf/tests/programs.rs
#	programs/bpf_loader/src/syscalls.rs
#	sdk/src/feature_set.rs

* resolve conflicts

Co-authored-by: Jack May <jack@solana.com>

sdk/program/src/program_memory.rs

@@ -0,0 +1,89 @@
+//! @brief Solana Rust-based BPF memory operations
+
+/// Memcpy
+///
+/// @param dst - Destination
+/// @param src - Source
+/// @param n - Number of bytes to copy
+#[inline]
+pub fn sol_memcpy(dst: &mut [u8], src: &[u8], n: usize) {
+    #[cfg(target_arch = "bpf")]
+    {
+        extern "C" {
+            fn sol_memcpy_(dst: *mut u8, src: *const u8, n: u64);
+        }
+        unsafe {
+            sol_memcpy_(dst.as_mut_ptr(), src.as_ptr(), n as u64);
+        }
+    }
+
+    #[cfg(not(target_arch = "bpf"))]
+    crate::program_stubs::sol_memcpy(dst.as_mut_ptr(), src.as_ptr(), n);
+}
+
+/// Memmove
+///
+/// @param dst - Destination
+/// @param src - Source
+/// @param n - Number of bytes to copy
+///
+/// # Safety
+#[inline]
+pub unsafe fn sol_memmove(dst: *mut u8, src: *mut u8, n: usize) {
+    #[cfg(target_arch = "bpf")]
+    {
+        extern "C" {
+            fn sol_memmove_(dst: *mut u8, src: *const u8, n: u64);
+        }
+        sol_memmove_(dst, src, n as u64);
+    }
+
+    #[cfg(not(target_arch = "bpf"))]
+    crate::program_stubs::sol_memmove(dst, src, n);
+}
+
+/// Memcmp
+///
+/// @param s1 - Slice to be compared
+/// @param s2 - Slice to be compared
+/// @param n - Number of bytes to compare
+#[inline]
+pub fn sol_memcmp(s1: &[u8], s2: &[u8], n: usize) -> i32 {
+    let mut result = 0;
+
+    #[cfg(target_arch = "bpf")]
+    {
+        extern "C" {
+            fn sol_memcmp_(s1: *const u8, s2: *const u8, n: u64, result: *mut i32);
+        }
+        unsafe {
+            sol_memcmp_(s1.as_ptr(), s2.as_ptr(), n as u64, &mut result as *mut i32);
+        }
+    }
+
+    #[cfg(not(target_arch = "bpf"))]
+    crate::program_stubs::sol_memcmp(s1.as_ptr(), s2.as_ptr(), n, &mut result as *mut i32);
+
+    result
+}
+
+/// Memset
+///
+/// @param s1 - Slice to be compared
+/// @param s2 - Slice to be compared
+/// @param n - Number of bytes to compare
+#[inline]
+pub fn sol_memset(s: &mut [u8], c: u8, n: usize) {
+    #[cfg(target_arch = "bpf")]
+    {
+        extern "C" {
+            fn sol_memset_(s: *mut u8, c: u8, n: u64);
+        }
+        unsafe {
+            sol_memset_(s.as_mut_ptr(), c, n as u64);
+        }
+    }
+
+    #[cfg(not(target_arch = "bpf"))]
+    crate::program_stubs::sol_memset(s.as_mut_ptr(), c, n);
+}