Revert "[Thumb] Reapply r272251 with a fix for PR28348"

This reverts commit r274510 - it made green dragon unhappy.

llvm-svn: 274512
This commit is contained in:
James Molloy 2016-07-04 17:14:24 +00:00
parent fdaed4c411
commit c3b4ed4a70
3 changed files with 1 additions and 69 deletions

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@ -2820,45 +2820,6 @@ void ARMDAGToDAGISel::Select(SDNode *N) {
if (tryV6T2BitfieldExtractOp(N, false))
return;
// If an immediate is used in an AND node, it is possible that the immediate
// can be more optimally materialized when negated. If this is the case we
// can negate the immediate and use a BIC instead.
auto *N1C = dyn_cast<ConstantSDNode>(N->getOperand(1));
if (N1C && N1C->hasOneUse() && Subtarget->isThumb()) {
uint32_t Imm = (uint32_t) N1C->getZExtValue();
// In Thumb2 mode, an AND can take a 12-bit immediate. If this
// immediate can be negated and fit in the immediate operand of
// a t2BIC, don't do any manual transform here as this can be
// handled by the generic ISel machinery.
bool PreferImmediateEncoding =
Subtarget->hasThumb2() && !is_t2_so_imm(Imm) && is_t2_so_imm_not(Imm);
if (!PreferImmediateEncoding &&
ConstantMaterializationCost(Imm) >
ConstantMaterializationCost(~Imm)) {
// The current immediate costs more to materialize than a negated
// immediate, so negate the immediate and use a BIC.
SDValue NewImm =
CurDAG->getTargetConstant(~N1C->getZExtValue(), dl, MVT::i32);
CurDAG->RepositionNode(N->getIterator(), NewImm.getNode());
if (!Subtarget->hasThumb2()) {
SDValue Ops[] = {CurDAG->getRegister(ARM::CPSR, MVT::i32),
N->getOperand(0), NewImm, getAL(CurDAG, dl),
CurDAG->getRegister(0, MVT::i32)};
ReplaceNode(N, CurDAG->getMachineNode(ARM::tBIC, dl, MVT::i32, Ops));
return;
} else {
SDValue Ops[] = {N->getOperand(0), NewImm, getAL(CurDAG, dl),
CurDAG->getRegister(0, MVT::i32),
CurDAG->getRegister(0, MVT::i32)};
ReplaceNode(N,
CurDAG->getMachineNode(ARM::t2BICri, dl, MVT::i32, Ops));
return;
}
}
}
// (and (or x, c2), c1) and top 16-bits of c1 and c2 match, lower 16-bits
// of c1 are 0xffff, and lower 16-bit of c2 are 0. That is, the top 16-bits
// are entirely contributed by c2 and lower 16-bits are entirely contributed
@ -2873,7 +2834,7 @@ void ARMDAGToDAGISel::Select(SDNode *N) {
if (!Opc)
break;
SDValue N0 = N->getOperand(0), N1 = N->getOperand(1);
N1C = dyn_cast<ConstantSDNode>(N1);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
if (!N1C)
break;
if (N0.getOpcode() == ISD::OR && N0.getNode()->hasOneUse()) {

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@ -1,12 +0,0 @@
; RUN: llc < %s -mtriple=thumbv7-linux-gnueabi -mcpu=cortex-m0 -verify-machineinstrs | FileCheck --check-prefix CHECK-T1 %s
; RUN: llc < %s -mtriple=thumbv7-linux-gnueabi -mcpu=cortex-m3 -verify-machineinstrs | FileCheck --check-prefix CHECK-T2 %s
; CHECK-T1-LABEL: @i
; CHECK-T2-LABEL: @i
; CHECK-T1: bics r0, #275
; CHECK-T2: bic r0, r0, #275
define i32 @i(i32 %a) {
entry:
%and = and i32 %a, -276
ret i32 %and
}

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@ -1,17 +0,0 @@
; RUN: llc < %s | FileCheck %s
target datalayout = "e-m:e-p:32:32-i1:8:32-i8:8:32-i16:16:32-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "thumbv7--linux-gnueabihf"
; CHECK-LABEL: f:
; CHECK: bic
define void @f(i32* nocapture %b, i32* nocapture %c, i32 %a) {
%1 = and i32 %a, -4096
store i32 %1, i32* %c, align 4
%2 = and i32 %a, 4095
%3 = or i32 %2, 4096
%4 = load i32, i32* %b, align 4
%5 = add nsw i32 %4, %3
store i32 %5, i32* %b, align 4
ret void
}