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Differential D109097

[X86] Remove isel predicates for xgetbv/xsetbv instructions so they can work on Windows.
ClosedPublic

Authored by craig.topper on Sep 1 2021, 2:57 PM.

Details

Reviewers
RKSimon
thakis
pengfei
Commits
rG3e89cc5cda22: [X86] Remove isel predicates for xgetbv/xsetbv instructions so they can work on…
Summary

https://reviews.llvm.org/D56686 was supposed to allow these to
work on Windows without needing to enable the xsave feature to
match MSVC. It seems this didn't work because the backend isel
patterns would still block it.

This patch removes the predicates from the isel patterns.

Fixes PR51706.

Diff Detail

Event Timeline

craig.topper created this revision.Sep 1 2021, 2:57 PM
Herald added a subscriber: hiraditya. · View Herald TranscriptSep 1 2021, 2:57 PM
craig.topper requested review of this revision.Sep 1 2021, 2:57 PM
Herald added a project: Restricted Project. · View Herald TranscriptSep 1 2021, 2:57 PM
Harbormaster completed remote builds in B122174: Diff 370075.Sep 1 2021, 3:26 PM
pengfei accepted this revision.Sep 2 2021, 9:37 AM

LGTM. Wild thought: is there any way that FE could handle it? e.g. append the xsave to function's feature attribute list for _xgetbv etc?

This revision is now accepted and ready to land.Sep 2 2021, 9:37 AM
This revision was landed with ongoing or failed builds.Sep 2 2021, 10:25 AM
Closed by commit rG3e89cc5cda22: [X86] Remove isel predicates for xgetbv/xsetbv instructions so they can work on… (authored by craig.topper). · Explain Why
This revision was automatically updated to reflect the committed changes.
craig.topper added a commit: rG3e89cc5cda22: [X86] Remove isel predicates for xgetbv/xsetbv instructions so they can work on….

Revision Contents

PathSize
llvm/
lib/
Target/
X86/
13 lines
test/
CodeGen/
X86/
4 lines

Diff 370319

llvm/lib/Target/X86/X86InstrSystem.td

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let SchedRW = [WriteSystem] in { let SchedRW = [WriteSystem] in {
def ENDBR64 : I<0x1E, MRM_FA, (outs), (ins), "endbr64", []>, XS; def ENDBR64 : I<0x1E, MRM_FA, (outs), (ins), "endbr64", []>, XS;
def ENDBR32 : I<0x1E, MRM_FB, (outs), (ins), "endbr32", []>, XS; def ENDBR32 : I<0x1E, MRM_FB, (outs), (ins), "endbr32", []>, XS;
} // SchedRW } // SchedRW
//===----------------------------------------------------------------------===// //===----------------------------------------------------------------------===//
// XSAVE instructions // XSAVE instructions
let SchedRW = [WriteSystem] in { let SchedRW = [WriteSystem] in {
let Predicates = [HasXSAVE] in { // NOTE: No HasXSAVE predicate so that these can be used with _xgetbv/_xsetbv
// on Windows without needing to enable the xsave feature to be compatible with
// MSVC.
let Defs = [EDX, EAX], Uses = [ECX] in let Defs = [EDX, EAX], Uses = [ECX] in
def XGETBV : I<0x01, MRM_D0, (outs), (ins), "xgetbv", []>, PS; def XGETBV : I<0x01, MRM_D0, (outs), (ins), "xgetbv", []>, PS;
let Uses = [EDX, EAX, ECX] in let Uses = [EDX, EAX, ECX] in
def XSETBV : I<0x01, MRM_D1, (outs), (ins), def XSETBV : I<0x01, MRM_D1, (outs), (ins),
"xsetbv", "xsetbv",
[(int_x86_xsetbv ECX, EDX, EAX)]>, PS; [(int_x86_xsetbv ECX, EDX, EAX)]>, PS;
} // HasXSAVE
let Uses = [EDX, EAX] in { let Uses = [EDX, EAX] in {
def XSAVE : I<0xAE, MRM4m, (outs), (ins opaquemem:$dst), def XSAVE : I<0xAE, MRM4m, (outs), (ins opaquemem:$dst),
"xsave\t$dst", "xsave\t$dst",
[(int_x86_xsave addr:$dst, EDX, EAX)]>, PS, Requires<[HasXSAVE]>; [(int_x86_xsave addr:$dst, EDX, EAX)]>, PS, Requires<[HasXSAVE]>;
def XSAVE64 : RI<0xAE, MRM4m, (outs), (ins opaquemem:$dst), def XSAVE64 : RI<0xAE, MRM4m, (outs), (ins opaquemem:$dst),
"xsave64\t$dst", "xsave64\t$dst",
[(int_x86_xsave64 addr:$dst, EDX, EAX)]>, PS, Requires<[HasXSAVE, In64BitMode]>; [(int_x86_xsave64 addr:$dst, EDX, EAX)]>, PS, Requires<[HasXSAVE, In64BitMode]>;
▲ Show 20 Lines • Show All 204 Lines • Show Last 20 Lines

llvm/test/CodeGen/X86/system-intrinsics-xsetbv.ll

; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+xsave | FileCheck %s ; RUN: llc < %s -mtriple=i686-unknown-unknown | FileCheck %s
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+xsave | FileCheck %s --check-prefix=CHECK64 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s --check-prefix=CHECK64
define void @test_xsetbv(i32 %in, i32 %high, i32 %low) { define void @test_xsetbv(i32 %in, i32 %high, i32 %low) {
; CHECK-LABEL: test_xsetbv ; CHECK-LABEL: test_xsetbv
; CHECK: movl 4(%esp), %ecx ; CHECK: movl 4(%esp), %ecx
; CHECK: movl 8(%esp), %edx ; CHECK: movl 8(%esp), %edx
; CHECK: movl 12(%esp), %eax ; CHECK: movl 12(%esp), %eax
; CHECK: xsetbv ; CHECK: xsetbv
; CHECK: ret ; CHECK: ret
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