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format: Emit XACQUIRE/XRELEASE

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As CMPXCHGD has a mandatory prefix table, it is absolutely necessary
that the presence of any tables does not modify any decoding state.
This commit is contained in:
Alexis Engelke
2021-01-23 14:35:08 +01:00
parent ab63a3c921
commit f17d84cee6
3 changed files with 43 additions and 2 deletions
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1
decode.c
View File

@@ -244,7 +244,6 @@ prefix_end:
// there is a REP prefix, then the 66h prefix is ignored here.
uint8_t mandatory_prefix = prefix_rep ? prefix_rep : !!prefix_66;
table_idx = table_walk(table_idx, mandatory_prefix, &kind);
prefix_rep = 0; // Don't include REP/REPNZ in instr flags
}
// Then, walk through ModR/M-encoded opcode extensions.

18
format.c
View File

@@ -125,6 +125,7 @@ fd_format_abs(const FdInstr* instr, uint64_t addr, char* buffer, size_t len)
const char* mnemonic = fdi_name(FD_TYPE(instr));
bool prefix_rep = false;
bool prefix_xacq_xrel = false;
bool prefix_addrsize = false;
bool prefix_segment = false;
@@ -183,6 +184,16 @@ fd_format_abs(const FdInstr* instr, uint64_t addr, char* buffer, size_t len)
FD_OP_REG_TYPE(instr, 0) == FD_RT_SEG)
sizesuffix[0] = 'w';
break;
case FDI_XCHG:
if (FD_OP_TYPE(instr, 0) == FD_OT_MEM)
prefix_xacq_xrel = true;
break;
case FDI_MOV:
// MOV C6h/C7h can have XRELEASE prefix.
if (FD_HAS_REP(instr) && FD_OP_TYPE(instr, 0) == FD_OT_MEM &&
FD_OP_TYPE(instr, 1) == FD_OT_IMM)
prefix_xacq_xrel = true;
break;
case FDI_FXSAVE:
case FDI_FXRSTOR:
case FDI_XSAVE:
@@ -217,7 +228,12 @@ fd_format_abs(const FdInstr* instr, uint64_t addr, char* buffer, size_t len)
default: break;
}
if (prefix_rep) {
if (prefix_xacq_xrel || FD_HAS_LOCK(instr)) {
if (FD_HAS_REP(instr))
buf = fd_strplcpy(buf, "xrelease ", end-buf);
if (FD_HAS_REPNZ(instr))
buf = fd_strplcpy(buf, "xacquire ", end-buf);
} else if (prefix_rep) {
if (FD_HAS_REP(instr))
buf = fd_strplcpy(buf, "rep ", end-buf);
if (FD_HAS_REPNZ(instr))

26
tests/test_decode.c
View File

@@ -90,6 +90,32 @@ main(int argc, char** argv)
TEST64("\xf2\x0f\xc7\x0f", "cmpxchg8b qword ptr [rdi]");
TEST32("\xf3\x0f\xc7\x0f", "cmpxchg8b qword ptr [edi]");
TEST64("\xf3\x0f\xc7\x0f", "cmpxchg8b qword ptr [rdi]");
TEST32("\xf2\xf0\x0f\xc7\x0f", "xacquire lock cmpxchg8b qword ptr [edi]");
TEST64("\xf2\xf0\x0f\xc7\x0f", "xacquire lock cmpxchg8b qword ptr [rdi]");
TEST32("\xf3\xf0\x0f\xc7\x0f", "xrelease lock cmpxchg8b qword ptr [edi]");
TEST64("\xf3\xf0\x0f\xc7\x0f", "xrelease lock cmpxchg8b qword ptr [rdi]");
TEST32("\x87\x0f", "xchg dword ptr [edi], ecx");
TEST64("\x87\x0f", "xchg dword ptr [rdi], ecx");
TEST32("\xf2\x87\x0f", "xacquire xchg dword ptr [edi], ecx");
TEST64("\xf2\x87\x0f", "xacquire xchg dword ptr [rdi], ecx");
TEST32("\xf3\x87\x0f", "xrelease xchg dword ptr [edi], ecx");
TEST64("\xf3\x87\x0f", "xrelease xchg dword ptr [rdi], ecx");
TEST32("\xf2\xf0\x87\x0f", "xacquire lock xchg dword ptr [edi], ecx");
TEST64("\xf2\xf0\x87\x0f", "xacquire lock xchg dword ptr [rdi], ecx");
TEST32("\xf3\xf0\x87\x0f", "xrelease lock xchg dword ptr [edi], ecx");
TEST64("\xf3\xf0\x87\x0f", "xrelease lock xchg dword ptr [rdi], ecx");
TEST32("\xc6\x07\x12", "mov byte ptr [edi], 0x12");
TEST64("\xc6\x07\x12", "mov byte ptr [rdi], 0x12");
TEST32("\xf2\xc6\x07\x12", "mov byte ptr [edi], 0x12"); // no xacquire
TEST64("\xf2\xc6\x07\x12", "mov byte ptr [rdi], 0x12"); // no xacquire
TEST32("\xf3\xc6\x07\x12", "xrelease mov byte ptr [edi], 0x12");
TEST64("\xf3\xc6\x07\x12", "xrelease mov byte ptr [rdi], 0x12");
TEST32("\x66\xc7\x07\x34\x12", "mov word ptr [edi], 0x1234");
TEST64("\x66\xc7\x07\x34\x12", "mov word ptr [rdi], 0x1234");
TEST32("\x66\xf2\xc7\x07\x34\x12", "mov word ptr [edi], 0x1234"); // no xacquire
TEST64("\x66\xf2\xc7\x07\x34\x12", "mov word ptr [rdi], 0x1234"); // no xacquire
TEST32("\x66\xf3\xc7\x07\x34\x12", "xrelease mov word ptr [edi], 0x1234");
TEST64("\x66\xf3\xc7\x07\x34\x12", "xrelease mov word ptr [rdi], 0x1234");
TEST("\x66", "PARTIAL");
TEST("\xf0", "PARTIAL");
TEST("\x0f", "PARTIAL");