[llvm] r206365 - DAGCombiner: don't optimise non-existant litpool load

Tim Northover tnorthover at apple.com
Wed Apr 16 02:03:10 PDT 2014


Author: tnorthover
Date: Wed Apr 16 04:03:09 2014
New Revision: 206365

URL: http://llvm.org/viewvc/llvm-project?rev=206365&view=rev
Log:
DAGCombiner: don't optimise non-existant litpool load

This particular DAG combine is designed to kick in when both ConstantFPs will
end up being loaded via a litpool, however those nodes have a semi-legal
status, dictated by isFPImmLegal so in some cases there wouldn't have been a
litpool in the first place. Don't try to be clever in those circumstances.

Picked up while merging some AArch64 tests.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    llvm/trunk/test/CodeGen/AArch64/regress-f128csel-flags.ll
    llvm/trunk/test/CodeGen/ARM64/fcmp-opt.ll

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=206365&r1=206364&r2=206365&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Wed Apr 16 04:03:09 2014
@@ -10942,7 +10942,9 @@ SDValue DAGCombiner::SimplifySelectCC(SD
     if (ConstantFPSDNode *FV = dyn_cast<ConstantFPSDNode>(N3)) {
       if (TLI.isTypeLegal(N2.getValueType()) &&
           (TLI.getOperationAction(ISD::ConstantFP, N2.getValueType()) !=
-           TargetLowering::Legal) &&
+               TargetLowering::Legal &&
+           !TLI.isFPImmLegal(TV->getValueAPF(), TV->getValueType(0)) &&
+           !TLI.isFPImmLegal(FV->getValueAPF(), FV->getValueType(0))) &&
           // If both constants have multiple uses, then we won't need to do an
           // extra load, they are likely around in registers for other users.
           (TV->hasOneUse() || FV->hasOneUse())) {

Modified: llvm/trunk/test/CodeGen/AArch64/regress-f128csel-flags.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AArch64/regress-f128csel-flags.ll?rev=206365&r1=206364&r2=206365&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AArch64/regress-f128csel-flags.ll (original)
+++ llvm/trunk/test/CodeGen/AArch64/regress-f128csel-flags.ll Wed Apr 16 04:03:09 2014
@@ -1,4 +1,5 @@
 ; RUN: llc -mtriple=aarch64-none-linux-gnu -verify-machineinstrs < %s | FileCheck %s
+; RUN: llc -mtriple=arm64-none-linux-gnu -verify-machineinstrs -o - %s | FileCheck %s
 
 ; We used to not mark NZCV as being used in the continuation basic-block
 ; when lowering a 128-bit "select" to branches. This meant a subsequent use

Modified: llvm/trunk/test/CodeGen/ARM64/fcmp-opt.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM64/fcmp-opt.ll?rev=206365&r1=206364&r2=206365&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM64/fcmp-opt.ll (original)
+++ llvm/trunk/test/CodeGen/ARM64/fcmp-opt.ll Wed Apr 16 04:03:09 2014
@@ -3,7 +3,7 @@
 
 define i1 @fcmp_float1(float %a) nounwind ssp {
 entry:
-; CHECK: @fcmp_float1
+; CHECK-LABEL: @fcmp_float1
 ; CHECK: fcmp s0, #0.0
 ; CHECK: csinc w0, wzr, wzr, eq
   %cmp = fcmp une float %a, 0.000000e+00
@@ -12,7 +12,7 @@ entry:
 
 define i1 @fcmp_float2(float %a, float %b) nounwind ssp {
 entry:
-; CHECK: @fcmp_float2
+; CHECK-LABEL: @fcmp_float2
 ; CHECK: fcmp s0, s1
 ; CHECK: csinc w0, wzr, wzr, eq
   %cmp = fcmp une float %a, %b
@@ -21,7 +21,7 @@ entry:
 
 define i1 @fcmp_double1(double %a) nounwind ssp {
 entry:
-; CHECK: @fcmp_double1
+; CHECK-LABEL: @fcmp_double1
 ; CHECK: fcmp d0, #0.0
 ; CHECK: csinc w0, wzr, wzr, eq
   %cmp = fcmp une double %a, 0.000000e+00
@@ -30,7 +30,7 @@ entry:
 
 define i1 @fcmp_double2(double %a, double %b) nounwind ssp {
 entry:
-; CHECK: @fcmp_double2
+; CHECK-LABEL: @fcmp_double2
 ; CHECK: fcmp d0, d1
 ; CHECK: csinc w0, wzr, wzr, eq
   %cmp = fcmp une double %a, %b
@@ -39,108 +39,137 @@ entry:
 
 ; Check each fcmp condition
 define float @fcmp_oeq(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_oeq
+; CHECK-LABEL: @fcmp_oeq
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, ne
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], eq
+
   %cmp = fcmp oeq float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_ogt(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ogt
+; CHECK-LABEL: @fcmp_ogt
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, le
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], gt
+
   %cmp = fcmp ogt float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_oge(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_oge
+; CHECK-LABEL: @fcmp_oge
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, lt
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], ge
+
   %cmp = fcmp oge float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_olt(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_olt
+; CHECK-LABEL: @fcmp_olt
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, pl
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], mi
+
   %cmp = fcmp olt float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_ole(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ole
+; CHECK-LABEL: @fcmp_ole
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, hi
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], ls
+
   %cmp = fcmp ole float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_ord(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ord
+; CHECK-LABEL: @fcmp_ord
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, vs
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], vc
   %cmp = fcmp ord float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_uno(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_uno
+; CHECK-LABEL: @fcmp_uno
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, vc
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], vs
   %cmp = fcmp uno float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_ugt(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ugt
+; CHECK-LABEL: @fcmp_ugt
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, ls
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], hi
   %cmp = fcmp ugt float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_uge(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_uge
+; CHECK-LABEL: @fcmp_uge
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, mi
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], pl
   %cmp = fcmp uge float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_ult(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ult
+; CHECK-LABEL: @fcmp_ult
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, ge
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], lt
   %cmp = fcmp ult float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_ule(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ule
+; CHECK-LABEL: @fcmp_ule
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, gt
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], le
   %cmp = fcmp ule float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
 }
 
 define float @fcmp_une(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_une
+; CHECK-LABEL: @fcmp_une
 ; CHECK: fcmp s0, s1
-; CHECK: csinc w{{[0-9]+}}, wzr, wzr, eq
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel s0, s[[ONE]], s[[ZERO]], ne
   %cmp = fcmp une float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
@@ -149,11 +178,12 @@ define float @fcmp_une(float %a, float %
 ; Possible opportunity for improvement.  See comment in
 ; ARM64TargetLowering::LowerSETCC()
 define float @fcmp_one(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_one
+; CHECK-LABEL: @fcmp_one
 ;	fcmp	s0, s1
-;	orr	w0, wzr, #0x1
-;	csel	w1, w0, wzr, mi
-;	csel	w0, w0, wzr, gt
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel [[TMP:s[0-9]+]], s[[ONE]], s[[ZERO]], mi
+; CHECK: fcsel s0, s[[ONE]], [[TMP]], gt
   %cmp = fcmp one float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv
@@ -162,11 +192,12 @@ define float @fcmp_one(float %a, float %
 ; Possible opportunity for improvement.  See comment in
 ; ARM64TargetLowering::LowerSETCC()
 define float @fcmp_ueq(float %a, float %b) nounwind ssp {
-; CHECK: @fcmp_ueq
+; CHECK-LABEL: @fcmp_ueq
 ; CHECK: fcmp s0, s1
-;        orr w0, wzr, #0x1
-; CHECK: csel [[REG1:w[0-9]]], [[REG2:w[0-9]+]], wzr, eq
-; CHECK: csel {{w[0-9]+}}, [[REG2]], [[REG1]], vs
+; CHECK-DAG: movi.2d v[[ZERO:[0-9]+]], #0
+; CHECK-DAG: fmov s[[ONE:[0-9]+]], #1.0
+; CHECK: fcsel [[TMP:s[0-9]+]], s[[ONE]], s[[ZERO]], eq
+; CHECK: fcsel s0, s[[ONE]], [[TMP]], vs
   %cmp = fcmp ueq float %a, %b
   %conv = uitofp i1 %cmp to float
   ret float %conv





More information about the llvm-commits mailing list