Commit 211fb91f authored by Craig Topper's avatar Craig Topper
Browse files

[DAGCombiner] Don't emit select_cc from visitSINT_TO_FP/visitUINT_TO_FP. Use plain select instead. 

Select_cc isn't used by all targets. X86 doesn't have optimizations
for it.

Since we already know the input to the sint_to_fp/uint_to_fp is
a setcc we can just emit a plain select using that setcc as the
condition. Other DAG combines can turn that into a select_cc on
targets that support it.

Differential Revision: https://reviews.llvm.org/D75415
parent 66128c48

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

+23 −39
Original line number Diff line number Diff line
@@ -13157,33 +13157,24 @@ SDValue DAGCombiner::visitSINT_TO_FP(SDNode *N) { 
  }















  // The next optimizations are desirable only if SELECT_CC can be lowered.













  if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, VT) || !LegalOperations) {













    // fold (sint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc)













  // fold (sint_to_fp (setcc x, y, cc)) -> (select (setcc x, y, cc), -1.0, 0.0)















  if (N0.getOpcode() == ISD::SETCC && N0.getValueType() == MVT::i1 &&















      !VT.isVector() &&













        (!LegalOperations ||













         TLI.isOperationLegalOrCustom(ISD::ConstantFP, VT))) {













      (!LegalOperations || TLI.isOperationLegalOrCustom(ISD::ConstantFP, VT))) {















    SDLoc DL(N);













      SDValue Ops[] =













        { N0.getOperand(0), N0.getOperand(1),













          DAG.getConstantFP(-1.0, DL, VT), DAG.getConstantFP(0.0, DL, VT),













          N0.getOperand(2) };













      return DAG.getNode(ISD::SELECT_CC, DL, VT, Ops);













    return DAG.getSelect(DL, VT, N0, DAG.getConstantFP(-1.0, DL, VT),













                         DAG.getConstantFP(0.0, DL, VT));















  }





























  // fold (sint_to_fp (zext (setcc x, y, cc))) ->













    //      (select_cc x, y, 1.0, 0.0,, cc)













  //      (select (setcc x, y, cc), 1.0, 0.0)















  if (N0.getOpcode() == ISD::ZERO_EXTEND &&















      N0.getOperand(0).getOpcode() == ISD::SETCC && !VT.isVector() &&













        (!LegalOperations ||













         TLI.isOperationLegalOrCustom(ISD::ConstantFP, VT))) {













      (!LegalOperations || TLI.isOperationLegalOrCustom(ISD::ConstantFP, VT))) {















    SDLoc DL(N);













      SDValue Ops[] =













        { N0.getOperand(0).getOperand(0), N0.getOperand(0).getOperand(1),













          DAG.getConstantFP(1.0, DL, VT), DAG.getConstantFP(0.0, DL, VT),













          N0.getOperand(0).getOperand(2) };













      return DAG.getNode(ISD::SELECT_CC, DL, VT, Ops);













    }













    return DAG.getSelect(DL, VT, N0.getOperand(0),













                         DAG.getConstantFP(1.0, DL, VT),













                         DAG.getConstantFP(0.0, DL, VT));















  }





























  if (SDValue FTrunc = foldFPToIntToFP(N, DAG, TLI))










@@ -13217,19 +13208,12 @@ SDValue DAGCombiner::visitUINT_TO_FP(SDNode *N) {













      return DAG.getNode(ISD::SINT_TO_FP, SDLoc(N), VT, N0);















  }



























  // The next optimizations are desirable only if SELECT_CC can be lowered.













  if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, VT) || !LegalOperations) {













    // fold (uint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc)













  // fold (uint_to_fp (setcc x, y, cc)) -> (select (setcc x, y, cc), 1.0, 0.0)















  if (N0.getOpcode() == ISD::SETCC && !VT.isVector() &&













        (!LegalOperations ||













         TLI.isOperationLegalOrCustom(ISD::ConstantFP, VT))) {













      (!LegalOperations || TLI.isOperationLegalOrCustom(ISD::ConstantFP, VT))) {















    SDLoc DL(N);













      SDValue Ops[] =













        { N0.getOperand(0), N0.getOperand(1),













          DAG.getConstantFP(1.0, DL, VT), DAG.getConstantFP(0.0, DL, VT),













          N0.getOperand(2) };













      return DAG.getNode(ISD::SELECT_CC, DL, VT, Ops);













    }













    return DAG.getSelect(DL, VT, N0, DAG.getConstantFP(1.0, DL, VT),













                         DAG.getConstantFP(0.0, DL, VT));















  }





























  if (SDValue FTrunc = foldFPToIntToFP(N, DAG, TLI))

































llvm/test/CodeGen/X86/cmovcmov.ll



+6
−16






























Original line number
Diff line number
Diff line








@@ -216,14 +216,9 @@ entry:













define float @test_zext_fcmp_une(float %a, float %b) nounwind {















; CMOV-LABEL: test_zext_fcmp_une:















; CMOV:       # %bb.0: # %entry













; CMOV-NEXT:    ucomiss %xmm1, %xmm0













; CMOV-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero













; CMOV-NEXT:    jne .LBB5_3













; CMOV-NEXT:  # %bb.1: # %entry













; CMOV-NEXT:    jp .LBB5_3













; CMOV-NEXT:  # %bb.2: # %entry













; CMOV-NEXT:    xorps %xmm0, %xmm0













; CMOV-NEXT:  .LBB5_3: # %entry













; CMOV-NEXT:    cmpneqss %xmm1, %xmm0













; CMOV-NEXT:    movss {{.*#+}} xmm1 = mem[0],zero,zero,zero













; CMOV-NEXT:    andps %xmm1, %xmm0















; CMOV-NEXT:    retq















;















; NOCMOV-LABEL: test_zext_fcmp_une:










@@ -259,14 +254,9 @@ entry:













define float @test_zext_fcmp_oeq(float %a, float %b) nounwind {















; CMOV-LABEL: test_zext_fcmp_oeq:















; CMOV:       # %bb.0: # %entry













; CMOV-NEXT:    ucomiss %xmm1, %xmm0













; CMOV-NEXT:    xorps %xmm0, %xmm0













; CMOV-NEXT:    jne .LBB6_3













; CMOV-NEXT:  # %bb.1: # %entry













; CMOV-NEXT:    jp .LBB6_3













; CMOV-NEXT:  # %bb.2: # %entry













; CMOV-NEXT:    movss {{.*#+}} xmm0 = mem[0],zero,zero,zero













; CMOV-NEXT:  .LBB6_3: # %entry













; CMOV-NEXT:    cmpeqss %xmm1, %xmm0













; CMOV-NEXT:    movss {{.*#+}} xmm1 = mem[0],zero,zero,zero













; CMOV-NEXT:    andps %xmm1, %xmm0















; CMOV-NEXT:    retq















;















; NOCMOV-LABEL: test_zext_fcmp_oeq:

































llvm/test/CodeGen/X86/pr44749.ll



+12
−24






























Original line number
Diff line number
Diff line








@@ -4,8 +4,8 @@













define i32 @a() {















; CHECK-LABEL: a:















; CHECK:       ## %bb.0: ## %entry













; CHECK-NEXT:    subq $40, %rsp













; CHECK-NEXT:    .cfi_def_cfa_offset 48













; CHECK-NEXT:    subq $24, %rsp













; CHECK-NEXT:    .cfi_def_cfa_offset 32















; CHECK-NEXT:    movsd {{.*#+}} xmm0 = mem[0],zero















; CHECK-NEXT:    movsd {{.*#+}} xmm1 = mem[0],zero















; CHECK-NEXT:    xorl %eax, %eax









@@ -16,31 +16,19 @@ define i32 @a() {













; CHECK-NEXT:    cvtsi2sd %eax, %xmm0















; CHECK-NEXT:    movq _calloc@{{.*}}(%rip), %rcx















; CHECK-NEXT:    subq $-1, %rcx













; CHECK-NEXT:    setne %dl













; CHECK-NEXT:    movzbl %dl, %eax













; CHECK-NEXT:    movl %eax, %esi













; CHECK-NEXT:    leaq {{.*}}(%rip), %rdi















; CHECK-NEXT:    movsd {{.*#+}} xmm1 = mem[0],zero













; CHECK-NEXT:    xorps %xmm2, %xmm2













; CHECK-NEXT:    movsd %xmm0, {{[-0-9]+}}(%r{{[sb]}}p) ## 8-byte Spill













; CHECK-NEXT:    movsd %xmm2, {{[-0-9]+}}(%r{{[sb]}}p) ## 8-byte Spill













; CHECK-NEXT:    movsd %xmm1, (%rsp) ## 8-byte Spill













; CHECK-NEXT:    jne LBB0_2













; CHECK-NEXT:  ## %bb.1: ## %entry













; CHECK-NEXT:    movsd {{[-0-9]+}}(%r{{[sb]}}p), %xmm0 ## 8-byte Reload













; CHECK-NEXT:    ## xmm0 = mem[0],zero













; CHECK-NEXT:    movsd %xmm0, (%rsp) ## 8-byte Spill













; CHECK-NEXT:  LBB0_2: ## %entry













; CHECK-NEXT:    movsd (%rsp), %xmm0 ## 8-byte Reload













; CHECK-NEXT:    ## xmm0 = mem[0],zero













; CHECK-NEXT:    movsd {{.*#+}} xmm1 = mem[0],zero













; CHECK-NEXT:    addsd %xmm1, %xmm0













; CHECK-NEXT:    movsd {{[-0-9]+}}(%r{{[sb]}}p), %xmm1 ## 8-byte Reload













; CHECK-NEXT:    ## xmm1 = mem[0],zero













; CHECK-NEXT:    ucomisd %xmm0, %xmm1













; CHECK-NEXT:    setae %al













; CHECK-NEXT:    movzbl %al, %ecx













; CHECK-NEXT:    movl %ecx, %edx













; CHECK-NEXT:    leaq {{.*}}(%rip), %rsi













; CHECK-NEXT:    ucomisd %xmm1, %xmm0













; CHECK-NEXT:    setae %dl













; CHECK-NEXT:    movzbl %dl, %eax













; CHECK-NEXT:    movl %eax, %esi













; CHECK-NEXT:    leaq {{.*}}(%rip), %rdi















; CHECK-NEXT:    movsd {{.*#+}} xmm0 = mem[0],zero















; CHECK-NEXT:    cvttsd2si %xmm0, %eax













; CHECK-NEXT:    addq $40, %rsp













; CHECK-NEXT:    addq $24, %rsp















; CHECK-NEXT:    retq















entry:















  %call = call i32 (...) @b()