Skip to content

[X86][MC] Check AdSize16 for 16-bit addressing #99761

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jul 20, 2024
Merged

[X86][MC] Check AdSize16 for 16-bit addressing #99761

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 4 additions & 1 deletion llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -691,9 +691,12 @@ void X86MCCodeEmitter::emitMemModRMByte(

unsigned BaseRegNo = BaseReg ? getX86RegNum(Base) : -1U;

bool IsAdSize16 = STI.hasFeature(X86::Is32Bit) &&
(TSFlags & X86II::AdSizeMask) == X86II::AdSize16;

// 16-bit addressing forms of the ModR/M byte have a different encoding for
// the R/M field and are far more limited in which registers can be used.
if (X86_MC::is16BitMemOperand(MI, Op, STI)) {
if (IsAdSize16 || X86_MC::is16BitMemOperand(MI, Op, STI)) {
if (BaseReg) {
// For 32-bit addressing, the row and column values in Table 2-2 are
// basically the same. It's AX/CX/DX/BX/SP/BP/SI/DI in that order, with
Expand Down
10 changes: 9 additions & 1 deletion llvm/test/MC/X86/x86-32-coverage.s
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10790,7 +10790,7 @@ btcl $4, (%eax)
movdir64b 485498096, %ecx

// CHECK: movdir64b 485498096, %cx
// CHECK: # encoding: [0x67,0x66,0x0f,0x38,0xf8,0x0d,0xf0,0x1c,0xf0,0x1c]
// CHECK: # encoding: [0x67,0x66,0x0f,0x38,0xf8,0x0e,0xf0,0x1c]
movdir64b 485498096, %cx

// CHECK: movdir64b (%edx), %eax
Expand Down Expand Up @@ -10877,6 +10877,10 @@ enqcmd (%bx,%di), %di
// CHECK: encoding: [0x67,0xf2,0x0f,0x38,0xf8,0x81,0xc0,0x1f]
enqcmd 8128(%bx,%di), %ax

// CHECK: enqcmd 485498096, %cx
// CHECK: encoding: [0x67,0xf2,0x0f,0x38,0xf8,0x0e,0xf0,0x1c]
enqcmd 485498096, %cx

// CHECK: enqcmds (%bx,%di), %di
// CHECK: encoding: [0x67,0xf3,0x0f,0x38,0xf8,0x39]
enqcmds (%bx,%di), %di
Expand All @@ -10885,6 +10889,10 @@ enqcmds (%bx,%di), %di
// CHECK: encoding: [0x67,0xf3,0x0f,0x38,0xf8,0x81,0xc0,0x1f]
enqcmds 8128(%bx,%di), %ax

// CHECK: enqcmds 485498096, %cx
// CHECK: encoding: [0x67,0xf3,0x0f,0x38,0xf8,0x0e,0xf0,0x1c]
enqcmds 485498096, %cx

// CHECK: serialize
// CHECK: encoding: [0x0f,0x01,0xe8]
serialize
Expand Down
Loading