Changeset 96626 in vbox

Timestamp:

Sep 7, 2022 11:36:22 AM (2 years ago)

Author:

vboxsync

Message:

VMM/IEM: Some fixes to the fucomi[p] instruction handling, need to update eflags register and the top of stack field in FSW correctly, bugref:9898

File:

• trunk/src/VBox/VMM/VMMAll/IEMAllCImpl.cpp (modified) (3 diffs)

trunk/src/VBox/VMM/VMMAll/IEMAllCImpl.cpp

@@ -9426 +9426 @@
     {
         uint32_t u32Eflags = pfnAImpl(pFpuCtx, &u16Fsw, &pFpuCtx->aRegs[0].r80, &pFpuCtx->aRegs[iStReg].r80);
-        NOREF(u32Eflags);
 
         pFpuCtx->FSW &= ~X86_FSW_C1;
@@ -9434 +9433 @@
         {
             pVCpu->cpum.GstCtx.eflags.u &= ~(X86_EFL_OF | X86_EFL_SF | X86_EFL_AF | X86_EFL_ZF | X86_EFL_PF | X86_EFL_CF);
-            pVCpu->cpum.GstCtx.eflags.u |= pVCpu->cpum.GstCtx.eflags.u & (X86_EFL_ZF | X86_EFL_PF | X86_EFL_CF);
+            pVCpu->cpum.GstCtx.eflags.u |= u32Eflags & (X86_EFL_ZF | X86_EFL_PF | X86_EFL_CF);
         }
     }
@@ -9461 +9460 @@
     {
         pFpuCtx->FTW &= ~RT_BIT(iReg1);
-        pFpuCtx->FSW &= X86_FSW_TOP_MASK;
-        pFpuCtx->FSW |= ((iReg1 + 7) & X86_FSW_TOP_SMASK) << X86_FSW_TOP_SHIFT;
+        iemFpuStackIncTop(pVCpu);
     }