SwitchEmu/dynarmic
1
0
Fork 0
mirror of https://git.suyu.dev/suyu/dynarmic.git synced 2026-03-07 14:26:28 +00:00
Code Issues Packages Projects Releases Wiki Activity

backend/x64: Reduce conversions required for cpsr_nzcv

Browse Source 
The guest program often accesses the NZCV flags directly much less
often than we need to use them for jumps and other such uses.

Therefore, we store our flags in cpsr_nzcv in a x64-friendly format.

This allows for a reduction in conditional jump related code.
This commit is contained in:
MerryMage
2020-05-06 22:08:38 +01:00
parent f4922a97f6
commit 8b3bc92bce
7 changed files with 213 additions and 189 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
src/backend/x64/a64_emit_x64.cpp
View File

@@ -15,6 +15,7 @@
#include "backend/x64/block_of_code.h"
#include "backend/x64/devirtualize.h"
#include "backend/x64/emit_x64.h"
#include "backend/x64/nzcv_util.h"
#include "backend/x64/perf_map.h"
#include "common/assert.h"
#include "common/bit_util.h"
@@ -371,7 +372,7 @@ void A64EmitX64::EmitA64SetCheckBit(A64EmitContext& ctx, IR::Inst* inst) {
void A64EmitX64::EmitA64GetCFlag(A64EmitContext& ctx, IR::Inst* inst) {
const Xbyak::Reg32 result = ctx.reg_alloc.ScratchGpr().cvt32();
code.mov(result, dword[r15 + offsetof(A64JitState, cpsr_nzcv)]);
code.shr(result, 29);
code.shr(result, NZCV::x64_c_flag_bit);
code.and_(result, 1);
ctx.reg_alloc.DefineValue(inst, result);
}
@@ -380,6 +381,9 @@ void A64EmitX64::EmitA64GetNZCVRaw(A64EmitContext& ctx, IR::Inst* inst) {
const Xbyak::Reg32 nzcv_raw = ctx.reg_alloc.ScratchGpr().cvt32();
code.mov(nzcv_raw, dword[r15 + offsetof(A64JitState, cpsr_nzcv)]);
code.and_(nzcv_raw, NZCV::x64_mask);
code.imul(nzcv_raw, nzcv_raw, NZCV::from_x64_multiplier);
code.and_(nzcv_raw, NZCV::arm_mask);
ctx.reg_alloc.DefineValue(inst, nzcv_raw);
}
@@ -387,17 +391,15 @@ void A64EmitX64::EmitA64SetNZCVRaw(A64EmitContext& ctx, IR::Inst* inst) {
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
const Xbyak::Reg32 nzcv_raw = ctx.reg_alloc.UseScratchGpr(args[0]).cvt32();
code.and_(nzcv_raw, 0xF0000000);
code.shr(nzcv_raw, 28);
code.imul(nzcv_raw, nzcv_raw, NZCV::to_x64_multiplier);
code.and_(nzcv_raw, NZCV::x64_mask);
code.mov(dword[r15 + offsetof(A64JitState, cpsr_nzcv)], nzcv_raw);
}
void A64EmitX64::EmitA64SetNZCV(A64EmitContext& ctx, IR::Inst* inst) {
auto args = ctx.reg_alloc.GetArgumentInfo(inst);
const Xbyak::Reg32 to_store = ctx.reg_alloc.UseScratchGpr(args[0]).cvt32();
code.and_(to_store, 0b11000001'00000001);
code.imul(to_store, to_store, 0b00010000'00100001);
code.shl(to_store, 16);
code.and_(to_store, 0xF0000000);
code.mov(dword[r15 + offsetof(A64JitState, cpsr_nzcv)], to_store);
}