diff --git a/.wolfssl_known_macro_extras b/.wolfssl_known_macro_extras
index ea4c8eaaa93..886354cfcc0 100644
--- a/.wolfssl_known_macro_extras
+++ b/.wolfssl_known_macro_extras
@@ -1110,6 +1110,7 @@ __must_check
 __ppc64__
 __ppc__
 __riscv
+__riscv_mul
 __riscv_xlen
 __s390x__
 __sparc
diff --git a/wolfcrypt/src/sp_arm32.c b/wolfcrypt/src/sp_arm32.c
index 4c9bedf6da0..72c224e7ae8 100644
--- a/wolfcrypt/src/sp_arm32.c
+++ b/wolfcrypt/src/sp_arm32.c
@@ -75620,7 +75620,9 @@ static void sp_256_get_entry_16_8(sp_point_256* r,
     r->y[6] = 0;
     r->y[7] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -76000,7 +76002,9 @@ static void sp_256_get_entry_256_8(sp_point_256* r,
     r->y[6] = 0;
     r->y[7] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -93643,7 +93647,9 @@ static void sp_384_get_entry_16_12(sp_point_384* r,
     r->y[10] = 0;
     r->y[11] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -94039,7 +94045,9 @@ static void sp_384_get_entry_256_12(sp_point_384* r,
     r->y[10] = 0;
     r->y[11] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -120766,7 +120774,9 @@ static void sp_521_get_entry_16_17(sp_point_521* r,
     r->y[15] = 0;
     r->y[16] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -121182,7 +121192,9 @@ static void sp_521_get_entry_256_17(sp_point_521* r,
     r->y[15] = 0;
     r->y[16] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
diff --git a/wolfcrypt/src/sp_armthumb.c b/wolfcrypt/src/sp_armthumb.c
index 14ec8f17d67..ab946469154 100644
--- a/wolfcrypt/src/sp_armthumb.c
+++ b/wolfcrypt/src/sp_armthumb.c
@@ -101072,7 +101072,9 @@ static void sp_256_get_entry_16_8(sp_point_256* r,
     r->y[6] = 0;
     r->y[7] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -101452,7 +101454,9 @@ static void sp_256_get_entry_256_8(sp_point_256* r,
     r->y[6] = 0;
     r->y[7] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -111495,7 +111499,9 @@ static void sp_384_get_entry_16_12(sp_point_384* r,
     r->y[10] = 0;
     r->y[11] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -111891,7 +111897,9 @@ static void sp_384_get_entry_256_12(sp_point_384* r,
     r->y[10] = 0;
     r->y[11] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -124705,7 +124713,9 @@ static void sp_521_get_entry_16_17(sp_point_521* r,
     r->y[15] = 0;
     r->y[16] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -125121,7 +125131,9 @@ static void sp_521_get_entry_256_17(sp_point_521* r,
     r->y[15] = 0;
     r->y[16] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
diff --git a/wolfcrypt/src/sp_c32.c b/wolfcrypt/src/sp_c32.c
index 44910f458cf..05256b3d6c5 100644
--- a/wolfcrypt/src/sp_c32.c
+++ b/wolfcrypt/src/sp_c32.c
@@ -114,6 +114,71 @@
 
 #ifndef WOLFSSL_SP_ASM
 #if SP_WORD_SIZE == 32
+#ifdef SP_NO_MUL_INSTRUCTION
+sp_uint64 __muldi3(sp_uint64 a, sp_uint64 b);
+sp_uint64 __muldi3(sp_uint64 a, sp_uint64 b)
+{
+    sp_uint64 r;
+    sp_uint64 am[16];
+
+    /* if b is negative, convert it to positive and negate a. */
+    r = 0 - (b >> 63);
+    a = a ^ r;
+    b = b ^ r;
+    a -= r;
+    b -= r;
+
+#if defined(WOLFSSL_SP_SMALL)
+    int i;
+
+    am[0] = 0;
+    for (i = 1; i < 16; i++) {
+        am[i] = am[i-1] + a;
+    }
+
+    r = am[(b >> 28) & 0xf];
+    for (i = 24; i >= 0; i -= 4) {
+        r <<= 4;
+        r += am[(b >> i) & 0xf];
+    }
+#else
+    am[ 0] = 0;
+    am[ 1] =          a;
+    am[ 2] = a << 1;
+    am[ 3] = am[ 2] + a;
+    am[ 4] = a << 2;
+    am[ 5] = am[ 4] + a;
+    am[ 6] = am[ 5] + a;
+    am[ 7] = am[ 6] + a;
+    am[ 8] = a << 3;
+    am[ 9] = am[ 8] + a;
+    am[10] = am[ 9] + a;
+    am[11] = am[10] + a;
+    am[12] = am[11] + a;
+    am[13] = am[12] + a;
+    am[14] = am[13] + a;
+    am[15] = am[14] + a;
+
+    r  = am[(b >> 28) & 0xf];
+    r <<= 4;
+    r += am[(b >> 24) & 0xf];
+    r <<= 4;
+    r += am[(b >> 20) & 0xf];
+    r <<= 4;
+    r += am[(b >> 16) & 0xf];
+    r <<= 4;
+    r += am[(b >> 12) & 0xf];
+    r <<= 4;
+    r += am[(b >>  8) & 0xf];
+    r <<= 4;
+    r += am[(b >>  4) & 0xf];
+    r <<= 4;
+    r += am[(b >>  0) & 0xf];
+#endif
+
+    return r;
+}
+#endif /* SP_NO_MUL_INSTRUCTION */
 #define SP_PRINT_NUM(var, name, total, words, bits)   \
     do {                                              \
         int ii;                                       \
@@ -21252,7 +21317,9 @@ static void sp_256_get_entry_256_9(sp_point_256* r,
     r->y[7] = 0;
     r->y[8] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -28357,7 +28424,9 @@ static void sp_384_get_entry_256_15(sp_point_384* r,
     r->y[13] = 0;
     r->y[14] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -35524,7 +35593,9 @@ static void sp_521_get_entry_256_21(sp_point_521* r,
     r->y[19] = 0;
     r->y[20] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
diff --git a/wolfcrypt/src/sp_c64.c b/wolfcrypt/src/sp_c64.c
index d3c08a73ac7..f4948e02033 100644
--- a/wolfcrypt/src/sp_c64.c
+++ b/wolfcrypt/src/sp_c64.c
@@ -21818,7 +21818,9 @@ static void sp_256_get_entry_256_5(sp_point_256* r,
     r->y[3] = 0;
     r->y[4] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint64)i - (sp_uint64)idx) >> 63) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint64)idx - (sp_uint64)i) >> 63) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -28358,7 +28360,9 @@ static void sp_384_get_entry_256_7(sp_point_384* r,
     r->y[5] = 0;
     r->y[6] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint64)i - (sp_uint64)idx) >> 63) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint64)idx - (sp_uint64)i) >> 63) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -35371,7 +35375,9 @@ static void sp_521_get_entry_256_9(sp_point_521* r,
     r->y[7] = 0;
     r->y[8] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint64)i - (sp_uint64)idx) >> 63) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint64)idx - (sp_uint64)i) >> 63) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
diff --git a/wolfcrypt/src/sp_cortexm.c b/wolfcrypt/src/sp_cortexm.c
index 975ed8b5092..9378e2b7903 100644
--- a/wolfcrypt/src/sp_cortexm.c
+++ b/wolfcrypt/src/sp_cortexm.c
@@ -37006,7 +37006,9 @@ static void sp_256_get_entry_16_8(sp_point_256* r,
     r->y[6] = 0;
     r->y[7] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -37386,7 +37388,9 @@ static void sp_256_get_entry_256_8(sp_point_256* r,
     r->y[6] = 0;
     r->y[7] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -46949,7 +46953,9 @@ static void sp_384_get_entry_16_12(sp_point_384* r,
     r->y[10] = 0;
     r->y[11] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -47345,7 +47351,9 @@ static void sp_384_get_entry_256_12(sp_point_384* r,
     r->y[10] = 0;
     r->y[11] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -58780,7 +58788,9 @@ static void sp_521_get_entry_16_17(sp_point_521* r,
     r->y[15] = 0;
     r->y[16] = 0;
     for (i = 1; i < 16; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
@@ -59196,7 +59206,9 @@ static void sp_521_get_entry_256_17(sp_point_521* r,
     r->y[15] = 0;
     r->y[16] = 0;
     for (i = 1; i < 256; i++) {
-        mask = (sp_digit)0 - (i == idx);
+        sp_digit gte = (sp_digit)((((sp_uint32)i - (sp_uint32)idx) >> 31) - 1);
+        sp_digit lte = (sp_digit)((((sp_uint32)idx - (sp_uint32)i) >> 31) - 1);
+        mask = gte & lte;
         r->x[0] |= mask & table[i].x[0];
         r->x[1] |= mask & table[i].x[1];
         r->x[2] |= mask & table[i].x[2];
diff --git a/wolfcrypt/src/sp_x86_64_asm.asm b/wolfcrypt/src/sp_x86_64_asm.asm
index d7575c33201..3f04d445c26 100644
--- a/wolfcrypt/src/sp_x86_64_asm.asm
+++ b/wolfcrypt/src/sp_x86_64_asm.asm
@@ -1,6 +1,6 @@
 ; /* sp_x86_64_asm.asm */
 ; /*
-; * Copyright (C) 2006-2026 wolfSSL Inc.
+;  * Copyright (C) 2006-2026 wolfSSL Inc.
 ;  *
 ;  * This file is part of wolfSSL.
 ;  *
diff --git a/wolfssl/wolfcrypt/sp.h b/wolfssl/wolfcrypt/sp.h
index c0f028a9b3a..9934a60e2a3 100644
--- a/wolfssl/wolfcrypt/sp.h
+++ b/wolfssl/wolfcrypt/sp.h
@@ -26,6 +26,10 @@
 #include <wolfssl/wolfcrypt/types.h>
 #include <wolfssl/wolfcrypt/settings.h>
 
+#if defined(__riscv) && (__riscv_xlen == 32) && !defined(__riscv_mul)
+    #define SP_NO_MUL_INSTRUCTION
+#endif
+
 #if defined(WOLFSSL_HAVE_SP_RSA) || defined(WOLFSSL_HAVE_SP_DH) || \
                                     defined(WOLFSSL_HAVE_SP_ECC)
 #ifdef _WIN32_WCE