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Differential D68356

[AArch64InstPrinter] prefer bfi to bfc for < armv8.2-a
ClosedPublic

Authored by nickdesaulniers on Oct 2 2019, 1:37 PM.

Details

Reviewers
t.p.northover
Commits
rG62a16ca77d68: Merging r373655:
rGede784ff5a60: [AArch64InstPrinter] prefer bfi to bfc for < armv8.2-a
rL373655: [AArch64InstPrinter] prefer bfi to bfc for < armv8.2-a
Summary

Fixes pr/42576.

Link: https://github.com/ClangBuiltLinux/linux/issues/697

Diff Detail

Event Timeline

nickdesaulniers created this revision.Oct 2 2019, 1:37 PM
Herald added a project: Restricted Project. · View Herald TranscriptOct 2 2019, 1:38 PM
Herald added subscribers: llvm-commits, hiraditya, kristof.beyls. · View Herald Transcript
nickdesaulniers updated this revision to Diff 222902.Oct 2 2019, 1:38 PM
  • git-clang-format HEAD~
Harbormaster completed remote builds in B38908: Diff 222901.Oct 2 2019, 1:39 PM
Harbormaster completed remote builds in B38909: Diff 222902.
t.p.northover accepted this revision.Oct 3 2019, 1:03 AM

Looks reasonable to me.

This revision is now accepted and ready to land.Oct 3 2019, 1:03 AM
nickdesaulniers edited the summary of this revision. (Show Details)Oct 3 2019, 8:58 AM
nickdesaulniers added a comment.Oct 3 2019, 9:45 AM

Sorry, this breaks:

Failing Tests (2):

LLVM :: MC/AArch64/basic-a64-instructions.s
LLVM :: MC/Disassembler/AArch64/basic-a64-instructions.txt

Let me fix those up then ask for re-review.

nickdesaulniers updated this revision to Diff 223045.Oct 3 2019, 10:00 AM
  • fix two unit tests that needed updating
Harbormaster completed remote builds in B38948: Diff 223045.Oct 3 2019, 10:01 AM
t.p.northover accepted this revision.Oct 3 2019, 10:33 AM

Fair enough. Still fine I think.

Closed by commit rL373655: [AArch64InstPrinter] prefer bfi to bfc for < armv8.2-a (authored by nickdesaulniers). · Explain WhyOct 3 2019, 1:11 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
lib/
Target/
AArch64/
MCTargetDesc/
2 lines
test/
MC/
AArch64/
11 lines

Diff 222901

llvm/lib/Target/AArch64/MCTargetDesc/AArch64InstPrinter.cpp

Show First 20 Lines • Show All 166 Lines • ▼ Show 20 Linesvoid AArch64InstPrinter::printInst(const MCInst *MI, raw_ostream &O,
if (Opcode == AArch64::BFMXri || Opcode == AArch64::BFMWri) { if (Opcode == AArch64::BFMXri || Opcode == AArch64::BFMWri) {
const MCOperand &Op0 = MI->getOperand(0); // Op1 == Op0 const MCOperand &Op0 = MI->getOperand(0); // Op1 == Op0
const MCOperand &Op2 = MI->getOperand(2); const MCOperand &Op2 = MI->getOperand(2);
int ImmR = MI->getOperand(3).getImm(); int ImmR = MI->getOperand(3).getImm();
int ImmS = MI->getOperand(4).getImm(); int ImmS = MI->getOperand(4).getImm();
if ((Op2.getReg() == AArch64::WZR || Op2.getReg() == AArch64::XZR) && if ((Op2.getReg() == AArch64::WZR || Op2.getReg() == AArch64::XZR) &&
(ImmR == 0 || ImmS < ImmR)) { (ImmR == 0 || ImmS < ImmR) && STI.getFeatureBits()[AArch64::HasV8_2aOps]) {
// BFC takes precedence over its entire range, sligtly differently to BFI. // BFC takes precedence over its entire range, sligtly differently to BFI.
int BitWidth = Opcode == AArch64::BFMXri ? 64 : 32; int BitWidth = Opcode == AArch64::BFMXri ? 64 : 32;
int LSB = (BitWidth - ImmR) % BitWidth; int LSB = (BitWidth - ImmR) % BitWidth;
int Width = ImmS + 1; int Width = ImmS + 1;
O << "\tbfc\t" << getRegisterName(Op0.getReg()) O << "\tbfc\t" << getRegisterName(Op0.getReg())
<< ", #" << LSB << ", #" << Width; << ", #" << LSB << ", #" << Width;
printAnnotation(O, Annot); printAnnotation(O, Annot);
▲ Show 20 Lines • Show All 1,404 Lines • Show Last 20 Lines

llvm/test/MC/AArch64/armv8.2a-bfc.s

  • This file was added.
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s | FileCheck %s --check-prefix=BFI
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s -mattr=+v8.1a | FileCheck %s --check-prefix=BFI
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s -mattr=-v8.2a | FileCheck %s --check-prefix=BFI
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s -mattr=+v8.2a | FileCheck %s --check-prefix=BFC
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s -mattr=+v8.3a | FileCheck %s --check-prefix=BFC
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s -mattr=+v8.4a | FileCheck %s --check-prefix=BFC
// RUN: llvm-mc -triple aarch64-linux-gnu -o - %s -mattr=+v8.5a | FileCheck %s --check-prefix=BFC
bfc w0, #1, #5
// BFI: bfi w0, wzr, #1, #5
// BFC: bfc w0, #1, #5