derek/gem5
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

arch-x86: Implement popping into a stack selector in real mode.

Browse Source 
Segmentation is relatively easy to deal with in real mode, vs. protected
mode.

Change-Id: I4b93a7e321d5debb7240b002bb42fdecaafbfdfe
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/55590
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This commit is contained in:
Gabe Black
2022-01-16 11:22:38 -08:00
parent c2c10dc647
commit 802f14bb52
3 changed files with 20 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
src/arch/x86/isa/decoder/one_byte_opcodes.isa
View File

@@ -47,6 +47,7 @@
}
0x7: decode MODE_SUBMODE {
0x0: UD2();
0x4: POP_REAL(sEv);
default: WarnUnimpl::pop_ES();
}
default: MultiInst::ADD(OPCODE_OP_BOTTOM3,
@@ -74,6 +75,7 @@
}
0x7: decode MODE_SUBMODE {
0x0: UD2();
0x4: POP_REAL(sSv);
default: WarnUnimpl::pop_SS();
}
default: MultiInst::ADC(OPCODE_OP_BOTTOM3,
@@ -88,6 +90,7 @@
}
0x7: decode MODE_SUBMODE {
0x0: UD2();
0x4: POP_REAL(sDv);
default: WarnUnimpl::pop_DS();
}
default: MultiInst::SBB(OPCODE_OP_BOTTOM3,

10
src/arch/x86/isa/decoder/two_byte_opcodes.isa
View File

@@ -668,7 +668,10 @@
}
0x14: decode OPCODE_OP_BOTTOM3 {
0x0: Inst::PUSH(sFv);
0x1: pop_fs();
0x1: decode MODE_SUBMODE {
0x4: Inst::POP_REAL(sFv);
default: pop_fs();
}
0x2: CPUIDInst::CPUID({{
CpuidResult result;
bool success = doCpuid(xc->tcBase(), bits(Rax, 31, 0),
@@ -695,7 +698,10 @@
}
0x15: decode OPCODE_OP_BOTTOM3 {
0x0: Inst::PUSH(sGv);
0x1: pop_gs();
0x1: decode MODE_SUBMODE {
0x4: Inst::POP_REAL(sGv);
default: pop_gs();
}
0x2: rsm_smm();
0x3: Inst::BTS(Ev,Gv);
0x4: Inst::SHRD(Ev,Gv,Ib);

9
src/arch/x86/isa/insts/general_purpose/data_transfer/stack_operations.py
View File

@@ -64,6 +64,15 @@ def macroop POP_P {
st t1, seg, riprel, disp
};
def macroop POP_REAL_S {
ld t1, ss, [1, t0, rsp], addressSize=ssz, dataSize=2
addi rsp, rsp, dsz, dataSize=ssz
wrsel sr, t1
mov t1, t0, t1, dataSize=2
slli t1, t1, 4, dataSize=8
wrbase sr, t1, dataSize=8
};
def macroop PUSH_R {
# Make the default data size of pops 64 bits in 64 bit mode
.adjust_env oszIn64Override