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Differential D80140

[x86] Propagate memory operands during ISel DAG postprocessing
ClosedPublic

Authored by Kayjukh on May 18 2020, 9:46 AM.

Details

Reviewers
craig.topper
rnk
lebedev.ri
Commits
rGcd12e79e6ddd: [x86] Propagate memory operands during ISel DAG postprocessing
Summary

Propagate memory operands when folding test instructions.

This was split from D80062.

Diff Detail

Revision Contents

PathSize
llvm/
lib/
Target/
X86/
2 lines
test/
CodeGen/
X86/
14 lines

Diff 264704

llvm/lib/Target/X86/X86ISelDAGToDAG.cpp

Show First 20 Lines • Show All 1,382 Lines • ▼ Show 20 Lines if ((Opc == X86::TEST8rr || Opc == X86::TEST16rr ||
And.getOperand(2), And.getOperand(2),
And.getOperand(3), And.getOperand(3),
And.getOperand(4), And.getOperand(4),
And.getOperand(5), And.getOperand(5),
And.getOperand(0), And.getOperand(0),
And.getOperand(6) /* Chain */ }; And.getOperand(6) /* Chain */ };
MachineSDNode *Test = CurDAG->getMachineNode(NewOpc, SDLoc(N), MachineSDNode *Test = CurDAG->getMachineNode(NewOpc, SDLoc(N),
MVT::i32, MVT::Other, Ops); MVT::i32, MVT::Other, Ops);
CurDAG->setNodeMemRefs(
Test, cast<MachineSDNode>(And.getNode())->memoperands());
ReplaceUses(N, Test); ReplaceUses(N, Test);
MadeChange = true; MadeChange = true;
continue; continue;
} }
} }
// Look for a KAND+KORTEST and turn it into KTEST if only the zero flag is // Look for a KAND+KORTEST and turn it into KTEST if only the zero flag is
// used. We're doing this late so we can prefer to fold the AND into masked // used. We're doing this late so we can prefer to fold the AND into masked
▲ Show 20 Lines • Show All 4,189 Lines • Show Last 20 Lines

llvm/test/CodeGen/X86/isel-postprocessing-test-fold-memop.ll

  • This file was added.
; RUN: llc -O2 -mtriple=x86_64-- -stop-after=finalize-isel < %s | FileCheck %s
define i1 @fold_test(i64* %x, i64 %l) {
entry:
%0 = load i64, i64* %x, align 8
%and = and i64 %0, %l
%tobool = icmp ne i64 %and, 0
ret i1 %tobool
; Folding the load+and+icmp instructions into a TEST64mr instruction
; should preserve memory operands.
; CHECK: TEST64mr {{.*}} :: (load 8 from {{%.*}})
}