Modified x86 register allocation

src/AssemblyGeneratorX86.cpp

@@ -24,9 +24,9 @@ along with RandomX.  If not, see<http://www.gnu.org/licenses/>.
 
 namespace RandomX {
 
-	static const char* regR[8] = { "rbx", "r9", "r10", "r11", "r12", "r13", "r14", "r15" };
+	static const char* regR[8] = { "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15" };
-	static const char* regR32[8] = { "ebx", "r9d", "r10d", "r11d", "r12d", "r13d", "r14d", "r15d" };
+	static const char* regR32[8] = { "r8d", "r9d", "r10d", "r11d", "r12d", "r13d", "r14d", "r15d" };
-	static const char* regF[8] = { "xmm8", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7" };
+	static const char* regF[8] = { "xmm8", "xmm9", "xmm2", "xmm3", "xmm4", "xmm5", "xmm6", "xmm7" };
 
 	void AssemblyGeneratorX86::generateProgram(const void* seed) {
 		asmCode.str(std::string()); //clear
@@ -149,8 +149,8 @@ namespace RandomX {
 			convertible_t bimm;
 			bimm.f64 = (double)instr.imm1;
 			asmCode << "\tmov rax, " << bimm.i64 << std::endl;
-			asmCode << "\tmovd xmm9, rax" << std::endl;
+			asmCode << "\tmovd xmm1, rax" << std::endl;
-			asmCode << "\t" << instrx86 << " xmm0, xmm9" << std::endl;
+			asmCode << "\t" << instrx86 << " xmm0, xmm1" << std::endl;
 			return;
 		}
 	}
@@ -262,12 +262,10 @@ namespace RandomX {
 
 	void AssemblyGeneratorX86::h_MULH_64(Instruction& instr, int i) {
 		gena(instr);
-		asmCode << "\tmov r8, rdx" << std::endl;
 		asmCode << "\tmov rcx, ";
 		genbr1(instr);
 		asmCode << "\tmul rcx" << std::endl;
 		asmCode << "\tmov rax, rdx" << std::endl;
-		asmCode << "\tmov rdx, r8" << std::endl;
 		gencr(instr);
 	}
 
@@ -295,18 +293,15 @@ namespace RandomX {
 
 	void AssemblyGeneratorX86::h_IMULH_64(Instruction& instr, int i) {
 		gena(instr);
-		asmCode << "\tmov r8, rdx" << std::endl;
 		asmCode << "\tmov rcx, ";
 		genbr1(instr);
 		asmCode << "\timul rcx" << std::endl;
 		asmCode << "\tmov rax, rdx" << std::endl;
-		asmCode << "\tmov rdx, r8" << std::endl;
 		gencr(instr);
 	}
 
 	void AssemblyGeneratorX86::h_DIV_64(Instruction& instr, int i) {
 		gena(instr);
-		asmCode << "\tmov r8, rdx" << std::endl;
 		if ((instr.locb & 7) >= 6) {
 			if (instr.imm1 == 0) {
 				asmCode << "\tmov ecx, 1" << std::endl;
@@ -323,13 +318,11 @@ namespace RandomX {
 		}
 		asmCode << "\txor edx, edx" << std::endl;
 		asmCode << "\tdiv rcx" << std::endl;
-		asmCode << "\tmov rdx, r8" << std::endl;
 		gencr(instr);
 	}
 
 	void AssemblyGeneratorX86::h_IDIV_64(Instruction& instr, int i) {
 		gena(instr);
-		asmCode << "\tmov r8, rdx" << std::endl;
 		asmCode << "\tmov edx, ";
 		genbr132(instr);
 		asmCode << "\tcmp edx, -1" << std::endl;
@@ -346,7 +339,6 @@ namespace RandomX {
 		asmCode << "\tcqo" << std::endl;
 		asmCode << "\tidiv rcx" << std::endl;
 		asmCode << "result_idiv_" << i << ":" << std::endl;
-		asmCode << "\tmov rdx, r8" << std::endl;
 		gencr(instr);
 	}
 

src/executeProgram-win64.asm

@@ -22,14 +22,14 @@ PUBLIC executeProgram
 executeProgram PROC
 	; REGISTER ALLOCATION:
 	; rax -> temporary
-	; rbx -> "r0"
+	; rbx -> MemoryRegisters& memory
 	; rcx -> temporary
-	; rdx -> MemoryRegisters& memory
+	; rdx -> temporary
 	; rsi -> convertible_t& scratchpad
 	; rdi -> "ic" (instruction counter)
 	; rbp	-> beginning of VM stack
 	; rsp -> end of VM stack
-	; r8 	-> temporary
+	; r8 	-> "r0"
 	; r9 	-> "r1"
 	; r10 -> "r2"
 	; r11 -> "r3"
@@ -38,7 +38,7 @@ executeProgram PROC
 	; r14 -> "r6"
 	; r15 -> "r7"
 	; xmm0 -> temporary
-	; xmm1 -> "f1"
+	; xmm1 -> temporary
 	; xmm2 -> "f2"
 	; xmm3 -> "f3"
 	; xmm4 -> "f4"
@@ -46,7 +46,7 @@ executeProgram PROC
 	; xmm6 -> "f6"
 	; xmm7 -> "f7"
 	; xmm8 -> "f0"
-	; xmm9 -> temporary
+	; xmm9 -> "f1"
 
 	; STACK STRUCTURE:
 	;   |
@@ -79,16 +79,16 @@ executeProgram PROC
 	movdqu xmmword ptr [rsp+0], xmm9
 
 	; function arguments
-	push rcx 				; RegisterFile& registerFile
+	push rcx				; RegisterFile& registerFile
-	; mov rdx, rdx	; MemoryRegisters& memory
+	mov rbx, rdx		; MemoryRegisters& memory
-	push r8 				; DatasetReadFunc readFunc
+	push r8					; DatasetReadFunc readFunc
 	mov rsi, r9			; convertible_t& scratchpad
 
-	mov rbp, rsp		; beginning of VM stack
+	mov rbp, rsp			; beginning of VM stack
 	mov rdi, 1048576	; number of VM instructions to execute
 
 	; load VM register values
-	mov rbx, qword ptr [rcx+0]
+	mov r8, qword ptr [rcx+0]
 	mov r9, qword ptr [rcx+8]
 	mov r10, qword ptr [rcx+16]
 	mov r11, qword ptr [rcx+24]
@@ -97,7 +97,7 @@ executeProgram PROC
 	mov r14, qword ptr [rcx+48]
 	mov r15, qword ptr [rcx+56]
 	movd xmm8, qword ptr [rcx+64]
-	movd xmm1, qword ptr [rcx+72]
+	movd xmm9, qword ptr [rcx+72]
 	movd xmm2, qword ptr [rcx+80]
 	movd xmm3, qword ptr [rcx+88]
 	movd xmm4, qword ptr [rcx+96]
@@ -116,7 +116,7 @@ rx_finish:
 
 	; save VM register values
 	mov rcx, qword ptr [rbp+8]
-	mov qword ptr [rcx+0], rbx
+	mov qword ptr [rcx+0], r8
 	mov qword ptr [rcx+8], r9
 	mov qword ptr [rcx+16], r10
 	mov qword ptr [rcx+24], r11
@@ -125,7 +125,7 @@ rx_finish:
 	mov qword ptr [rcx+48], r14
 	mov qword ptr [rcx+56], r15
 	movd qword ptr [rcx+64], xmm8
-	movd qword ptr [rcx+72], xmm1
+	movd qword ptr [rcx+72], xmm9
 	movd qword ptr [rcx+80], xmm2
 	movd qword ptr [rcx+88], xmm3
 	movd qword ptr [rcx+96], xmm4
@@ -170,19 +170,18 @@ rx_read_dataset_light:
 	ret 0
 
 rx_read_dataset:
-	mov r8d, dword ptr [rdx]	; ma
+	mov edx, dword ptr [rbx]	; ma
-	mov rax, qword ptr [rdx+8]	; dataset
+	mov rax, qword ptr [rbx+8]	; dataset
-	mov rax, qword ptr [rax+r8]
+	mov rax, qword ptr [rax+rdx]
-	add dword ptr [rdx], 8
+	add dword ptr [rbx], 8
-	mov r8d, dword ptr [rdx+4]	; mx
+	xor ecx, dword ptr [rbx+4]	; mx
-	xor ecx, r8d
+	mov dword ptr [rbx+4], ecx
-	mov dword ptr [rdx+4], ecx
 	test ecx, 0FFF8h
 	jne short rx_read_dataset_full_ret
 	and ecx, -8
-	mov dword ptr [rdx], ecx
+	mov dword ptr [rbx], ecx
-	mov r8, qword ptr [rdx+8]
+	mov rdx, qword ptr [rbx+8]
-	prefetcht0 byte ptr [r8+rcx]
+	prefetcht0 byte ptr [rdx+rcx]
 rx_read_dataset_full_ret:
 	ret 0
 executeProgram ENDP