Zvk: Implement Zvksh, vector SM3 Hash Function

Implement the Zvksh sub-extension, "ShangMi Suite: SM3 Hash
Function Instructions":
 - vsm3me.vv, message expansion,
 - vsm3c.vi, compression rounds.

This also introduces a SM3 specific header for common logic.

Co-authored-by: Raghav Gupta <rgupta@rivosinc.com>
Co-authored-by: Albert Jakieła <aja@semihalf.com>
Co-authored-by: Kornel Dulęba <mindal@semihalf.com>
Signed-off-by: Eric Gouriou <ego@rivosinc.com>

4 files changed, 151 insertions, 0 deletions

diff --git a/riscv/insns/vsm3c_vi.h b/riscv/insns/vsm3c_vi.h
new file mode 100644
index 0000000..b3e8121
--- /dev/null
+++ b/riscv/insns/vsm3c_vi.h
@@ -0,0 +1,60 @@
+// vsm3c.vi vd, vs2, rnd
+
+#include "zvksh_ext_macros.h"
+
+require_vsm3_constraints;
+
+VI_ZVK_VD_VS2_ZIMM5_EGU32x8_NOVM_LOOP(
+  {},
+  // No need to validate or normalize 'zimm5' here as this is a 5 bits value
+  // and all values in 0-31 are valid.
+  const reg_t round = zimm5;,
+  {
+    // {H, G, F, E, D, C, B, A} <- vd
+    EXTRACT_EGU32x8_WORDS_BE_BSWAP(vd, H, G, F, E, D, C, B, A);
+    // {_, _, w5, w4, _, _, w1, w0} <- vs2
+    EXTRACT_EGU32x8_WORDS_BE_BSWAP(vs2,
+                                   UNUSED _unused_w7, UNUSED _unused_w6, w5, w4,
+                                   UNUSED _unused_w3, UNUSED _unused_w2, w1, w0);
+    const uint32_t x0 = w0 ^ w4;  // W'[0] in spec documentation.
+    const uint32_t x1 = w1 ^ w5;  // W'[1]
+
+    // Two rounds of compression.
+    uint32_t ss1;
+    uint32_t ss2;
+    uint32_t tt1;
+    uint32_t tt2;
+    uint32_t j;
+
+    j = 2 * round;
+    ss1 = ZVK_ROL32(ZVK_ROL32(A, 12) + E + ZVK_ROL32(ZVKSH_T(j), j % 32), 7);
+    ss2 = ss1 ^ ZVK_ROL32(A, 12);
+    tt1 = ZVKSH_FF(A, B, C, j) + D + ss2 + x0;
+    tt2 = ZVKSH_GG(E, F, G, j) + H + ss1 + w0;
+    D = C;
+    const uint32_t C1 = ZVK_ROL32(B, 9);
+    B = A;
+    const uint32_t A1 = tt1;
+    H = G;
+    const uint32_t G1 = ZVK_ROL32(F, 19);
+    F = E;
+    const uint32_t E1 = ZVKSH_P0(tt2);
+
+    j = 2 * round + 1;
+    ss1 = ZVK_ROL32(ZVK_ROL32(A1, 12) + E1 + ZVK_ROL32(ZVKSH_T(j), j % 32), 7);
+    ss2 = ss1 ^ ZVK_ROL32(A1, 12);
+    tt1 = ZVKSH_FF(A1, B, C1, j) + D + ss2 + x1;
+    tt2 = ZVKSH_GG(E1, F, G1, j) + H + ss1 + w1;
+    D = C1;
+    const uint32_t C2 = ZVK_ROL32(B, 9);
+    B = A1;
+    const uint32_t A2 = tt1;
+    H = G1;
+    const uint32_t G2 = ZVK_ROL32(F, 19);
+    F = E1;
+    const uint32_t E2 = ZVKSH_P0(tt2);
+
+    // Update the destination register.
+    SET_EGU32x8_WORDS_BE_BSWAP(vd, G1, G2, E1, E2, C1, C2, A1, A2);
+  }
+);
diff --git a/riscv/insns/vsm3me_vv.h b/riscv/insns/vsm3me_vv.h
new file mode 100644
index 0000000..dd6cb52
--- /dev/null
+++ b/riscv/insns/vsm3me_vv.h
@@ -0,0 +1,39 @@
+// vsm3me.vv vd, vs2, vs1
+
+#include "zvk_ext_macros.h"
+#include "zvksh_ext_macros.h"
+
+// Per the SM3 spec, the message expansion computes new words Wi as:
+//   W[i] = (    P_1( W[i-16] xor W[i-9] xor ( W[i-3] <<< 15 ) )
+//           xor ( W[i-13] <<< 7 )
+//           xor W[i-6]))
+// Using arguments M16 = W[i-16], M9 = W[i-9], etc.,
+// where Mk stands for "W[i Minus k]", we define the "W function":
+#define ZVKSH_W(M16, M9, M3, M13, M6) \
+  (ZVKSH_P1((M16) ^  (M9) ^ ZVK_ROL32((M3), 15)) ^ ZVK_ROL32((M13), 7) ^ (M6))
+
+require_vsm3_constraints;
+
+VI_ZVK_VD_VS1_VS2_EGU32x8_NOVM_LOOP(
+  {},
+  {
+    // {w7,  w6,  w5,  w4,  w3,  w2,  w1,  w0} <- vs1
+    EXTRACT_EGU32x8_WORDS_BE_BSWAP(vs1, w7, w6, w5, w4, w3, w2, w1, w0);
+    // {w15, w14, w13, w12, w11, w10, w9, w8} <- vs2
+    EXTRACT_EGU32x8_WORDS_BE_BSWAP(vs2, w15, w14, w13, w12, w11, w10, w9, w8);
+
+    // Arguments are W[i-16], W[i-9], W[i-13], W[i-6].
+    // Note that some of the newly computed words are used in later invocations.
+    const uint32_t w16 = ZVKSH_W(w0,  w7, w13,  w3, w10);
+    const uint32_t w17 = ZVKSH_W(w1,  w8, w14,  w4, w11);
+    const uint32_t w18 = ZVKSH_W(w2,  w9, w15,  w5, w12);
+    const uint32_t w19 = ZVKSH_W(w3, w10, w16,  w6, w13);
+    const uint32_t w20 = ZVKSH_W(w4, w11, w17,  w7, w14);
+    const uint32_t w21 = ZVKSH_W(w5, w12, w18,  w8, w15);
+    const uint32_t w22 = ZVKSH_W(w6, w13, w19,  w9, w16);
+    const uint32_t w23 = ZVKSH_W(w7, w14, w20, w10, w17);
+
+    // Update the destination register.
+    SET_EGU32x8_WORDS_BE_BSWAP(vd, w23, w22, w21, w20, w19, w18, w17, w16);
+  }
+);
diff --git a/riscv/riscv.mk.in b/riscv/riscv.mk.in
index c774e1b..a3e125f 100644
--- a/riscv/riscv.mk.in
+++ b/riscv/riscv.mk.in
@@ -1392,6 +1392,10 @@ riscv_insn_ext_zvksed = \
 	vsm4r_vs \
 	vsm4r_vv \
 
+riscv_insn_ext_zvksh = \
+	vsm3c_vi \
+	vsm3me_vv \
+
 riscv_insn_ext_zvk = \
 	$(riscv_insn_ext_zvbb) \
 	$(riscv_insn_ext_zvbc) \
@@ -1399,6 +1403,7 @@ riscv_insn_ext_zvk = \
 	$(riscv_insn_ext_zvkned) \
 	$(riscv_insn_ext_zvknh) \
 	$(riscv_insn_ext_zvksed) \
+	$(riscv_insn_ext_zvksh) \
 
 riscv_insn_list = \
 	$(if $(HAVE_INT128),$(riscv_insn_ext_v),) \
diff --git a/riscv/zvksh_ext_macros.h b/riscv/zvksh_ext_macros.h
new file mode 100644
index 0000000..71c5a09
--- /dev/null
+++ b/riscv/zvksh_ext_macros.h
@@ -0,0 +1,47 @@
+// Helper macros and functions to help implement instructions defined as part of
+// the RISC-V Zvksh extension (vectorized SM3).
+
+#include "zvk_ext_macros.h"
+
+#ifndef RISCV_INSNS_ZVKSH_COMMON_H_
+#define RISCV_INSNS_ZVKSH_COMMON_H_
+
+// Constraints common to all vsm3* instructions:
+//  - Zvksh is enabled
+//  - VSEW == 32
+//  - EGW (256) <= LMUL * VLEN
+//  - No overlap of vd and vs2.
+//
+// The constraint that vstart and vl are both EGS (8) aligned
+// is checked in the VI_ZVK_..._EGU32x8_..._LOOP macros.
+#define require_vsm3_constraints \
+  do { \
+    require_zvksh; \
+    require(P.VU.vsew == 32); \
+    require_egw_fits(256); \
+    require(insn.rd() != insn.rs2()); \
+  } while (false)
+
+#define FF1(X, Y, Z) ((X) ^ (Y) ^ (Z))
+#define FF2(X, Y, Z) (((X) & (Y)) | ((X) & (Z)) | ((Y) & (Z)))
+
+// Boolean function FF_j - section 4.3. of the IETF draft.
+#define ZVKSH_FF(X, Y, Z, J) (((J) <= 15) ? FF1(X, Y, Z) : FF2(X, Y, Z))
+
+#define GG1(X, Y, Z) ((X) ^ (Y) ^ (Z))
+#define GG2(X, Y, Z) (((X) & (Y)) | ((~(X)) & (Z)))
+
+// Boolean function GG_j - section 4.3. of the IETF draft.
+#define ZVKSH_GG(X, Y, Z, J) (((J) <= 15) ? GG1(X, Y, Z) : GG2(X, Y, Z))
+
+#define T1 0x79CC4519
+#define T2 0x7A879D8A
+
+// T_j constant - section 4.2. of the IETF draft.
+#define ZVKSH_T(J) (((J) <= 15) ? (T1) : (T2))
+
+// Permutation functions P_0 and P_1 - section 4.4 of the IETF draft.
+#define ZVKSH_P0(X) ((X) ^ ZVK_ROL32((X),  9) ^ ZVK_ROL32((X), 17))
+#define ZVKSH_P1(X) ((X) ^ ZVK_ROL32((X), 15) ^ ZVK_ROL32((X), 23))
+
+#endif // RISCV_INSNS_ZVKSH_COMMON_H