core/crypto/sha2: Clean up the portable code slightly

core/crypto/sha2/sha2.odin

@@ -271,7 +271,7 @@ reset :: proc(ctx: ^$T) {
 */
 
 @(private, rodata)
-sha256_k := [64]u32 {
+SHA256_K := [64]u32 {
 	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
 	0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
 	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
@@ -291,7 +291,7 @@ sha256_k := [64]u32 {
 }
 
 @(private, rodata)
-sha512_k := [80]u64 {
+SHA512_K := [80]u64 {
 	0x428a2f98d728ae22, 0x7137449123ef65cd,
 	0xb5c0fbcfec4d3b2f, 0xe9b5dba58189dbbc,
 	0x3956c25bf348b538, 0x59f111f1b605d019,
@@ -334,6 +334,11 @@ sha512_k := [80]u64 {
 	0x5fcb6fab3ad6faec, 0x6c44198c4a475817,
 }
 
+@(private)
+SHA256_ROUNDS :: 64
+@(private)
+SHA512_ROUNDS :: 80
+
 @(private)
 SHA256_CH :: #force_inline proc "contextless" (x, y, z: u32) -> u32 {
 	return (x & y) ~ (~x & z)
@@ -395,27 +400,29 @@ SHA512_F4 :: #force_inline proc "contextless" (x: u64) -> u64 {
 }
 
 @(private)
-sha2_transf :: proc "contextless" (ctx: ^$T, data: []byte) {
+sha2_transf :: proc "contextless" (ctx: ^$T, data: []byte) #no_bounds_check {
 	when T == Context_256 {
 		if is_hardware_accelerated_256() {
 			sha256_transf_hw(ctx, data)
 			return
 		}
 
-		w: [64]u32
+		w: [SHA256_ROUNDS]u32
 		wv: [8]u32
 		t1, t2: u32
+
 		CURR_BLOCK_SIZE :: BLOCK_SIZE_256
 	} else when T == Context_512 {
-		w: [80]u64
+		w: [SHA512_ROUNDS]u64
 		wv: [8]u64
 		t1, t2: u64
+
 		CURR_BLOCK_SIZE :: BLOCK_SIZE_512
 	}
 
 	data := data
 	for len(data) >= CURR_BLOCK_SIZE {
-		for i := 0; i < 16; i += 1 {
+		for i in 0 ..< 16 {
 			when T == Context_256 {
 				w[i] = endian.unchecked_get_u32be(data[i * 4:])
 			} else when T == Context_512 {
@@ -424,22 +431,22 @@ sha2_transf :: proc "contextless" (ctx: ^$T, data: []byte) {
 		}
 
 		when T == Context_256 {
-			for i := 16; i < 64; i += 1 {
+			for i in 16 ..< SHA256_ROUNDS {
 				w[i] = SHA256_F4(w[i - 2]) + w[i - 7] + SHA256_F3(w[i - 15]) + w[i - 16]
 			}
 		} else when T == Context_512 {
-			for i := 16; i < 80; i += 1 {
+			for i in 16 ..< SHA512_ROUNDS {
 				w[i] = SHA512_F4(w[i - 2]) + w[i - 7] + SHA512_F3(w[i - 15]) + w[i - 16]
 			}
 		}
 
-		for i := 0; i < 8; i += 1 {
+		for i in 0 ..< 8 {
 			wv[i] = ctx.h[i]
 		}
 
 		when T == Context_256 {
-			for i := 0; i < 64; i += 1 {
-				t1 = wv[7] + SHA256_F2(wv[4]) + SHA256_CH(wv[4], wv[5], wv[6]) + sha256_k[i] + w[i]
+			for i in 0 ..< SHA256_ROUNDS {
+				t1 = wv[7] + SHA256_F2(wv[4]) + SHA256_CH(wv[4], wv[5], wv[6]) + SHA256_K[i] + w[i]
 				t2 = SHA256_F1(wv[0]) + SHA256_MAJ(wv[0], wv[1], wv[2])
 				wv[7] = wv[6]
 				wv[6] = wv[5]
@@ -451,8 +458,8 @@ sha2_transf :: proc "contextless" (ctx: ^$T, data: []byte) {
 				wv[0] = t1 + t2
 			}
 		} else when T == Context_512 {
-			for i := 0; i < 80; i += 1 {
-				t1 = wv[7] + SHA512_F2(wv[4]) + SHA512_CH(wv[4], wv[5], wv[6]) + sha512_k[i] + w[i]
+			for i in 0 ..< SHA512_ROUNDS {
+				t1 = wv[7] + SHA512_F2(wv[4]) + SHA512_CH(wv[4], wv[5], wv[6]) + SHA512_K[i] + w[i]
 				t2 = SHA512_F1(wv[0]) + SHA512_MAJ(wv[0], wv[1], wv[2])
 				wv[7] = wv[6]
 				wv[6] = wv[5]
@@ -465,7 +472,7 @@ sha2_transf :: proc "contextless" (ctx: ^$T, data: []byte) {
 			}
 		}
 
-		for i := 0; i < 8; i += 1 {
+		for i in 0 ..< 8 {
 			ctx.h[i] += wv[i]
 		}