Clarifications/corrections in the specification/comments

Removed some unused code

src/assembly_generator_x86.hpp

@@ -58,7 +58,6 @@ namespace randomx {
 		void h_ISMULH_R(Instruction&, int);
 		void h_ISMULH_M(Instruction&, int);
 		void h_IMUL_RCP(Instruction&, int);
-		void h_ISDIV_C(Instruction&, int);
 		void h_INEG_R(Instruction&, int);
 		void h_IXOR_R(Instruction&, int);
 		void h_IXOR_M(Instruction&, int);

src/jit_compiler_x86.cpp

@@ -72,7 +72,7 @@ namespace randomx {
 	REGISTER ALLOCATION:
 
 	; rax -> temporary
-	; rbx -> loop counter "lc"
+	; rbx -> iteration counter "ic"
 	; rcx -> temporary
 	; rdx -> temporary
 	; rsi -> scratchpad pointer
@@ -100,9 +100,9 @@ namespace randomx {
 	; xmm10 -> "a2"
 	; xmm11 -> "a3"
 	; xmm12 -> temporary
-	; xmm13 -> mantissa mask    = 0x000fffffffffffff000fffffffffffff
-	; xmm14 -> exponent 2**-240 = 0x30f00000000xxxxx30f00000000xxxxx
-	; xmm15 -> scale mask       = 0x81f000000000000081f0000000000000
+	; xmm13 -> E 'and' mask = 0x00ffffffffffffff00ffffffffffffff
+	; xmm14 -> E 'or' mask  = 0x3*00000000******3*00000000******
+	; xmm15 -> scale mask   = 0x81f000000000000081f0000000000000
 
 	*/
 
@@ -444,7 +444,7 @@ namespace randomx {
 		emit32(instr.getModMem() ? ScratchpadL1Mask : ScratchpadL2Mask);
 	}
 
-	void JitCompilerX86::genAddressRegDst(Instruction& instr, bool align16 = false) {
+	void JitCompilerX86::genAddressRegDst(Instruction& instr) {
 		emit(LEA_32);
 		emitByte(0x80 + instr.dst);
 		if (instr.dst == RegisterNeedsSib) {
@@ -453,9 +453,7 @@ namespace randomx {
 		emit32(instr.getImm32());
 		emitByte(AND_EAX_I);
 		if (instr.getModCond() < StoreL3Condition) {
-			int32_t maskL1 = align16 ? ScratchpadL1Mask16 : ScratchpadL1Mask;
-			int32_t maskL2 = align16 ? ScratchpadL2Mask16 : ScratchpadL2Mask;
-			emit32(instr.getModMem() ? maskL1 : maskL2);
+			emit32(instr.getModMem() ? ScratchpadL1Mask : ScratchpadL2Mask);
 		}
 		else {
 			emit32(ScratchpadL3Mask);

src/jit_compiler_x86.hpp

@@ -65,7 +65,7 @@ namespace randomx {
 		void generateProgramPrologue(Program&, ProgramConfiguration&);
 		void generateProgramEpilogue(Program&);
 		void genAddressReg(Instruction&, bool);
-		void genAddressRegDst(Instruction&, bool);
+		void genAddressRegDst(Instruction&);
 		void genAddressImm(Instruction&);
 		void genSIB(int scale, int index, int base);
 

src/reciprocal.c

@@ -21,6 +21,7 @@ along with RandomX.  If not, see<http://www.gnu.org/licenses/>.
 
 /*
 	Calculates rcp = 2**x / divisor for highest integer x such that rcp < 2**64.
+	divisor must not be 0 or a power of 2
 
 	Equivalent x86 assembly (divisor in rcx):