Optimized x86 initialization

src/CompiledVirtualMachine.cpp

@@ -29,10 +29,6 @@ namespace RandomX {
 		for (unsigned i = 0; i < sizeof(reg) / sizeof(Pcg32::result_type); ++i) {
 			*(((uint32_t*)&reg) + i) = gen();
 		}
-		FPINIT();
-		for (int i = 0; i < 8; ++i) {
-			reg.f[i].f64 = (double)reg.f[i].i64;
-		}
 		for (unsigned i = 0; i < ProgramLength; ++i) {
 			gen(); gen(); gen(); gen();
 		}
@@ -41,7 +37,6 @@ namespace RandomX {
 	}
 
 	void CompiledVirtualMachine::execute() {
-		FPINIT();
 		executeProgram(reg, mem, readDataset, scratchpad);
 #ifdef TRACE
 		for (int32_t i = InstructionCount - 1; i >= 0; --i) {

src/executeProgram-win64.asm

@@ -96,14 +96,16 @@ executeProgram PROC
 	mov r13, qword ptr [rcx+40]
 	mov r14, qword ptr [rcx+48]
 	mov r15, qword ptr [rcx+56]
-	movd xmm8, qword ptr [rcx+64]
-	movd xmm9, qword ptr [rcx+72]
-	movd xmm2, qword ptr [rcx+80]
-	movd xmm3, qword ptr [rcx+88]
-	movd xmm4, qword ptr [rcx+96]
-	movd xmm5, qword ptr [rcx+104]
-	movd xmm6, qword ptr [rcx+112]
-	movd xmm7, qword ptr [rcx+120]
+	mov dword ptr [rsp - 8], 40896
+	ldmxcsr dword ptr [rsp - 8]
+	cvtsi2sd xmm8, qword ptr [rcx+64]
+	cvtsi2sd xmm9, qword ptr [rcx+72]
+	cvtsi2sd xmm2, qword ptr [rcx+80]
+	cvtsi2sd xmm3, qword ptr [rcx+88]
+	cvtsi2sd xmm4, qword ptr [rcx+96]
+	cvtsi2sd xmm5, qword ptr [rcx+104]
+	cvtsi2sd xmm6, qword ptr [rcx+112]
+	cvtsi2sd xmm7, qword ptr [rcx+120]
 
 	; program body