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Revert "[DAG] Fold (shl (sext (add_nsw x, c1)), c2) -> (add (shl (sext x), c2), c1 << c2)"
This reverts commit b027ce0. This commit breaks Transforms/InferAddressSpaces/AMDGPU/flat_atomic.ll.
1 parent fdb29f7 commit 97bf104

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4 files changed

+8
-30
lines changed

4 files changed

+8
-30
lines changed

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

Lines changed: 0 additions & 21 deletions
Original file line numberDiff line numberDiff line change
@@ -10009,27 +10009,6 @@ SDValue DAGCombiner::visitSHL(SDNode *N) {
1000910009
}
1001010010
}
1001110011

10012-
// fold (shl (sext (add_nsw x, c1)), c2) -> (add (shl (sext x), c2), c1 << c2)
10013-
// TODO: Add zext/add_nuw variant with suitable test coverage
10014-
// TODO: Should we limit this with isLegalAddImmediate?
10015-
if (N0.getOpcode() == ISD::SIGN_EXTEND &&
10016-
N0.getOperand(0).getOpcode() == ISD::ADD &&
10017-
N0.getOperand(0)->getFlags().hasNoSignedWrap() && N0->hasOneUse() &&
10018-
N0.getOperand(0)->hasOneUse() &&
10019-
TLI.isDesirableToCommuteWithShift(N, Level)) {
10020-
SDValue Add = N0.getOperand(0);
10021-
SDLoc DL(N0);
10022-
if (SDValue ExtC = DAG.FoldConstantArithmetic(N0.getOpcode(), DL, VT,
10023-
{Add.getOperand(1)})) {
10024-
if (SDValue ShlC =
10025-
DAG.FoldConstantArithmetic(ISD::SHL, DL, VT, {ExtC, N1})) {
10026-
SDValue ExtX = DAG.getNode(N0.getOpcode(), DL, VT, Add.getOperand(0));
10027-
SDValue ShlX = DAG.getNode(ISD::SHL, DL, VT, ExtX, N1);
10028-
return DAG.getNode(ISD::ADD, DL, VT, ShlX, ShlC);
10029-
}
10030-
}
10031-
}
10032-
1003310012
// fold (shl (mul x, c1), c2) -> (mul x, c1 << c2)
1003410013
if (N0.getOpcode() == ISD::MUL && N0->hasOneUse()) {
1003510014
SDValue N01 = N0.getOperand(1);

llvm/test/CodeGen/AArch64/arm64-shifted-sext.ll

Lines changed: 2 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -275,9 +275,8 @@ entry:
275275
define i64 @extendedLeftShiftintToint64By4(i32 %a) nounwind readnone ssp {
276276
; CHECK-LABEL: extendedLeftShiftintToint64By4:
277277
; CHECK: ; %bb.0: ; %entry
278-
; CHECK-NEXT: ; kill: def $w0 killed $w0 def $x0
279-
; CHECK-NEXT: sbfiz x8, x0, #4, #32
280-
; CHECK-NEXT: add x0, x8, #16
278+
; CHECK-NEXT: add w8, w0, #1
279+
; CHECK-NEXT: sbfiz x0, x8, #4, #32
281280
; CHECK-NEXT: ret
282281
entry:
283282
%inc = add nsw i32 %a, 1

llvm/test/CodeGen/AArch64/arm64-trunc-store.ll

Lines changed: 4 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -20,10 +20,10 @@ define void @fct32(i32 %arg, i64 %var) {
2020
; CHECK-LABEL: fct32:
2121
; CHECK: // %bb.0: // %bb
2222
; CHECK-NEXT: adrp x8, :got:zptr32
23+
; CHECK-NEXT: sub w9, w0, #1
2324
; CHECK-NEXT: ldr x8, [x8, :got_lo12:zptr32]
2425
; CHECK-NEXT: ldr x8, [x8]
25-
; CHECK-NEXT: add x8, x8, w0, sxtw #2
26-
; CHECK-NEXT: stur w1, [x8, #-4]
26+
; CHECK-NEXT: str w1, [x8, w9, sxtw #2]
2727
; CHECK-NEXT: ret
2828
bb:
2929
%.pre37 = load ptr, ptr @zptr32, align 8
@@ -39,10 +39,10 @@ define void @fct16(i32 %arg, i64 %var) {
3939
; CHECK-LABEL: fct16:
4040
; CHECK: // %bb.0: // %bb
4141
; CHECK-NEXT: adrp x8, :got:zptr16
42+
; CHECK-NEXT: sub w9, w0, #1
4243
; CHECK-NEXT: ldr x8, [x8, :got_lo12:zptr16]
4344
; CHECK-NEXT: ldr x8, [x8]
44-
; CHECK-NEXT: add x8, x8, w0, sxtw #1
45-
; CHECK-NEXT: sturh w1, [x8, #-2]
45+
; CHECK-NEXT: strh w1, [x8, w9, sxtw #1]
4646
; CHECK-NEXT: ret
4747
bb:
4848
%.pre37 = load ptr, ptr @zptr16, align 8

llvm/test/CodeGen/X86/addr-mode-matcher-2.ll

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -52,8 +52,8 @@ define void @foo_sext_nsw(i1 zeroext, i32) nounwind {
5252
; X64-NEXT: .p2align 4, 0x90
5353
; X64-NEXT: .LBB0_2: # =>This Inner Loop Header: Depth=1
5454
; X64-NEXT: cltq
55-
; X64-NEXT: shlq $2, %rax
56-
; X64-NEXT: leaq 20(%rax,%rax,4), %rdi
55+
; X64-NEXT: leaq 4(,%rax,4), %rax
56+
; X64-NEXT: leaq (%rax,%rax,4), %rdi
5757
; X64-NEXT: callq bar@PLT
5858
; X64-NEXT: jmp .LBB0_2
5959
br i1 %0, label %9, label %3

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