SelectionDAG: Add sext_inreg optimizations

v2: use dyn_cast
    fixup comments
v3: use cast

Reviewed-by: Matt Arsenault <arsenm2@gmail.com>
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220044 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jan Vesely 2014-10-17 14:45:25 +00:00
parent eaf8f5efe9
commit cef793e8c7
2 changed files with 48 additions and 0 deletions

View File

@ -1680,6 +1680,17 @@ SDValue DAGCombiner::visitADD(SDNode *N) {
return DAG.getNode(ISD::SUB, DL, VT, N1, ZExt);
}
// add X, (sextinreg Y i1) -> sub X, (and Y 1)
if (N1.getOpcode() == ISD::SIGN_EXTEND_INREG) {
VTSDNode *TN = cast<VTSDNode>(N1.getOperand(1));
if (TN->getVT() == MVT::i1) {
SDLoc DL(N);
SDValue ZExt = DAG.getNode(ISD::AND, DL, VT, N1.getOperand(0),
DAG.getConstant(1, VT));
return DAG.getNode(ISD::SUB, DL, VT, N0, ZExt);
}
}
return SDValue();
}
@ -1845,6 +1856,17 @@ SDValue DAGCombiner::visitSUB(SDNode *N) {
VT);
}
// sub X, (sextinreg Y i1) -> add X, (and Y 1)
if (N1.getOpcode() == ISD::SIGN_EXTEND_INREG) {
VTSDNode *TN = cast<VTSDNode>(N1.getOperand(1));
if (TN->getVT() == MVT::i1) {
SDLoc DL(N);
SDValue ZExt = DAG.getNode(ISD::AND, DL, VT, N1.getOperand(0),
DAG.getConstant(1, VT));
return DAG.getNode(ISD::ADD, DL, VT, N0, ZExt);
}
}
return SDValue();
}

View File

@ -0,0 +1,26 @@
; RUN: llc -march=r600 -mcpu=cypress -verify-machineinstrs < %s | FileCheck -check-prefix=EG -check-prefix=FUNC %s
; FUNC-LABEL: {{^}}sext_in_reg_i1_i32_add:
; EG: MEM_{{.*}} STORE_{{.*}} [[RES:T[0-9]+\.[XYZW]]], [[ADDR:T[0-9]+.[XYZW]]]
; EG: SUB_INT {{[* ]*}}[[RES]]
; EG-NOT: BFE
define void @sext_in_reg_i1_i32_add(i32 addrspace(1)* %out, i1 %a, i32 %b) {
%sext = sext i1 %a to i32
%res = add i32 %b, %sext
store i32 %res, i32 addrspace(1)* %out
ret void
}
; FUNC-LABEL: {{^}}sext_in_reg_i1_i32_sub:
; EG: MEM_{{.*}} STORE_{{.*}} [[RES:T[0-9]+\.[XYZW]]], [[ADDR:T[0-9]+.[XYZW]]]
; EG: ADD_INT {{[* ]*}}[[RES]]
; EG-NOT: BFE
define void @sext_in_reg_i1_i32_sub(i32 addrspace(1)* %out, i1 %a, i32 %b) {
%sext = sext i1 %a to i32
%res = sub i32 %b, %sext
store i32 %res, i32 addrspace(1)* %out
ret void
}