riscv: P extension intrinsics for packed SIMD (part 1)

Implement by inline assembly for now, uses `pure, nomem, nostack` for
all packed simd arithmetic instructions. Uses `inlateout` when it
requires using the same register for input and output, use `lateout`
for all output registers.

This commit also includes a rearrangement of shared risc-v architecture
module to improve documents. It also includes a doc test fix, gate sm3/4
and use explict sm3/4 instruction under rustc target feature.

Author: luojia65

crates/core_arch/src/lib.rs

@@ -19,6 +19,7 @@
     doc_cfg,
     tbm_target_feature,
     sse4a_target_feature,
+    riscv_target_feature,
     arm_target_feature,
     cmpxchg16b_target_feature,
     avx512_target_feature,

crates/core_arch/src/mod.rs

@@ -3,6 +3,9 @@
 #[macro_use]
 mod macros;
 
+#[cfg(any(target_arch = "riscv32", target_arch = "riscv64", doc))]
+mod riscv_shared;
+
 #[cfg(any(target_arch = "arm", target_arch = "aarch64", doc))]
 mod arm_shared;
 
@@ -276,10 +279,6 @@ mod aarch64;
 #[doc(cfg(any(target_arch = "arm")))]
 mod arm;
 
-#[cfg(any(target_arch = "riscv32", target_arch = "riscv64", doc))]
-#[doc(cfg(any(target_arch = "riscv32", target_arch = "riscv64")))]
-mod riscv_shared;
-
 #[cfg(any(target_arch = "riscv64", doc))]
 #[doc(cfg(any(target_arch = "riscv64")))]
 mod riscv64;

crates/core_arch/src/riscv_shared/mod.rs

@@ -1,4 +1,7 @@
 //! Shared RISC-V intrinsics
+mod p;
+
+pub use p::*;
 
 use crate::arch::asm;
 
@@ -602,12 +605,10 @@ pub unsafe fn hinval_gvma_all() {
 /// According to RISC-V Cryptography Extensions, Volume I, the execution latency of
 /// this instruction must always be independent from the data it operates on.
 #[inline]
+#[target_feature(enable = "zksh")]
 pub fn sm3p0(x: u32) -> u32 {
     let ans: u32;
-    unsafe {
-        // asm!("sm3p0 {}, {}", out(reg) ans, in(reg) x, options(nomem, nostack))
-        asm!(".insn i 0x13, 0x1, {}, {}, 0x108", out(reg) ans, in(reg) x, options(nomem, nostack))
-    };
+    unsafe { asm!("sm3p0 {}, {}", lateout(reg) ans, in(reg) x, options(pure, nomem, nostack)) };
     ans
 }
 
@@ -634,12 +635,10 @@ pub fn sm3p0(x: u32) -> u32 {
 /// According to RISC-V Cryptography Extensions, Volume I, the execution latency of
 /// this instruction must always be independent from the data it operates on.
 #[inline]
+#[target_feature(enable = "zksh")]
 pub fn sm3p1(x: u32) -> u32 {
     let ans: u32;
-    unsafe {
-        // asm!("sm3p1 {}, {}", out(reg) ans, in(reg) x, options(nomem, nostack))
-        asm!(".insn i 0x13, 0x1, {}, {}, 0x109", out(reg) ans, in(reg) x, options(nomem, nostack))
-    };
+    unsafe { asm!("sm3p1 {}, {}", lateout(reg) ans, in(reg) x, options(pure, nomem, nostack)) };
     ans
 }
 
@@ -674,33 +673,28 @@ pub fn sm3p1(x: u32) -> u32 {
 /// It can be implemented by `sm4ed` instruction like:
 ///
 /// ```no_run
+/// # #[cfg(any(target_arch = "riscv32", target_arch = "riscv64"))]
+/// # fn round_function(x0: u32, x1: u32, x2: u32, x3: u32, rk: u32) -> u32 {
+/// # #[cfg(target_arch = "riscv32")] use core::arch::riscv32::sm4ed;
+/// # #[cfg(target_arch = "riscv64")] use core::arch::riscv64::sm4ed;
 /// let a = x1 ^ x2 ^ x3 ^ rk;
 /// let c0 = sm4ed::<0>(x0, a);
 /// let c1 = sm4ed::<1>(c0, a); // c1 represents c[0..=1], etc.
 /// let c2 = sm4ed::<2>(c1, a);
 /// let c3 = sm4ed::<3>(c2, a);
 /// return c3; // c3 represents c[0..=3]
+/// # }
 /// ```
 ///
 /// According to RISC-V Cryptography Extensions, Volume I, the execution latency of
 /// this instruction must always be independent from the data it operates on.
+#[inline]
+#[target_feature(enable = "zksed")]
 pub fn sm4ed<const BS: u8>(x: u32, a: u32) -> u32 {
     static_assert!(BS: u8 where BS <= 3);
     let ans: u32;
-    match BS {
-        0 => unsafe {
-            asm!(".insn r 0x33, 0, 0x18, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) a, options(nomem, nostack))
-        },
-        1 => unsafe {
-            asm!(".insn r 0x33, 0, 0x38, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) a, options(nomem, nostack))
-        },
-        2 => unsafe {
-            asm!(".insn r 0x33, 0, 0x58, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) a, options(nomem, nostack))
-        },
-        3 => unsafe {
-            asm!(".insn r 0x33, 0, 0x78, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) a, options(nomem, nostack))
-        },
-        _ => unreachable!(),
+    unsafe {
+        asm!("sm4ed {}, {}, {}, {}", lateout(reg) ans, in(reg) x, in(reg) k, const BS, options(pure, nomem, nostack))
     };
     ans
 }
@@ -739,33 +733,28 @@ pub fn sm4ed<const BS: u8>(x: u32, a: u32) -> u32 {
 /// Hence, the key schedule operation can be implemented by `sm4ks` instruction like:
 ///
 /// ```no_run
+/// # #[cfg(any(target_arch = "riscv32", target_arch = "riscv64"))]
+/// # fn key_schedule(k0: u32, k1: u32, k2: u32, k3: u32, ck_i: u32) -> u32 {
+/// # #[cfg(target_arch = "riscv32")] use core::arch::riscv32::sm4ks;
+/// # #[cfg(target_arch = "riscv64")] use core::arch::riscv64::sm4ks;
 /// let k = k1 ^ k2 ^ k3 ^ ck_i;
 /// let c0 = sm4ks::<0>(k0, k);
 /// let c1 = sm4ks::<1>(c0, k); // c1 represents c[0..=1], etc.
 /// let c2 = sm4ks::<2>(c1, k);
 /// let c3 = sm4ks::<3>(c2, k);
 /// return c3; // c3 represents c[0..=3]
+/// # }
 /// ```
 ///
 /// According to RISC-V Cryptography Extensions, Volume I, the execution latency of
 /// this instruction must always be independent from the data it operates on.
+#[inline]
+#[target_feature(enable = "zksed")]
 pub fn sm4ks<const BS: u8>(x: u32, k: u32) -> u32 {
     static_assert!(BS: u8 where BS <= 3);
     let ans: u32;
-    match BS {
-        0 => unsafe {
-            asm!(".insn r 0x33, 0, 0x1A, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) k, options(nomem, nostack))
-        },
-        1 => unsafe {
-            asm!(".insn r 0x33, 0, 0x3A, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) k, options(nomem, nostack))
-        },
-        2 => unsafe {
-            asm!(".insn r 0x33, 0, 0x5A, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) k, options(nomem, nostack))
-        },
-        3 => unsafe {
-            asm!(".insn r 0x33, 0, 0x7A, {}, {}, {}", out(reg) ans, in(reg) x, in(reg) k, options(nomem, nostack))
-        },
-        _ => unreachable!(),
+    unsafe {
+        asm!("sm4ks {}, {}, {}, {}", lateout(reg) ans, in(reg) x, in(reg) k, const BS, options(pure, nomem, nostack))
     };
     ans
 }