[llvm] r206153 - Revert r206045, "Fix shift by constants for vector."

NAKAMURA Takumi geek4civic at gmail.com
Mon Apr 14 00:02:57 PDT 2014


Author: chapuni
Date: Mon Apr 14 02:02:57 2014
New Revision: 206153

URL: http://llvm.org/viewvc/llvm-project?rev=206153&view=rev
Log:
Revert r206045, "Fix shift by constants for vector."

It broke some builders, at least, i686.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombine.h
    llvm/trunk/lib/Transforms/InstCombine/InstCombineShifts.cpp
    llvm/trunk/test/Transforms/InstCombine/shift.ll

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombine.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombine.h?rev=206153&r1=206152&r2=206153&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombine.h (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombine.h Mon Apr 14 02:02:57 2014
@@ -171,7 +171,7 @@ public:
                                 ICmpInst::Predicate Pred);
   Instruction *FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
                            ICmpInst::Predicate Cond, Instruction &I);
-  Instruction *FoldShiftByConstant(Value *Op0, Constant *Op1,
+  Instruction *FoldShiftByConstant(Value *Op0, ConstantInt *Op1,
                                    BinaryOperator &I);
   Instruction *commonCastTransforms(CastInst &CI);
   Instruction *commonPointerCastTransforms(CastInst &CI);

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineShifts.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineShifts.cpp?rev=206153&r1=206152&r2=206153&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineShifts.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineShifts.cpp Mon Apr 14 02:02:57 2014
@@ -33,7 +33,7 @@ Instruction *InstCombiner::commonShiftTr
       if (Instruction *R = FoldOpIntoSelect(I, SI))
         return R;
 
-  if (Constant *CUI = dyn_cast<Constant>(Op1))
+  if (ConstantInt *CUI = dyn_cast<ConstantInt>(Op1))
     if (Instruction *Res = FoldShiftByConstant(Op0, CUI, I))
       return Res;
 
@@ -309,30 +309,20 @@ static Value *GetShiftedValue(Value *V,
 
 
 
-Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, Constant *Op1,
+Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, ConstantInt *Op1,
                                                BinaryOperator &I) {
   bool isLeftShift = I.getOpcode() == Instruction::Shl;
 
-  ConstantInt *COp1 = nullptr;
-  if (ConstantDataVector *CV = dyn_cast<ConstantDataVector>(Op1))
-    COp1 = dyn_cast_or_null<ConstantInt>(CV->getSplatValue());
-  else if (ConstantVector *CV = dyn_cast<ConstantVector>(Op1))
-    COp1 = dyn_cast_or_null<ConstantInt>(CV->getSplatValue());
-  else
-    COp1 = dyn_cast<ConstantInt>(Op1);
-
-  if (!COp1)
-    return nullptr;
 
   // See if we can propagate this shift into the input, this covers the trivial
   // cast of lshr(shl(x,c1),c2) as well as other more complex cases.
   if (I.getOpcode() != Instruction::AShr &&
-      CanEvaluateShifted(Op0, COp1->getZExtValue(), isLeftShift, *this)) {
+      CanEvaluateShifted(Op0, Op1->getZExtValue(), isLeftShift, *this)) {
     DEBUG(dbgs() << "ICE: GetShiftedValue propagating shift through expression"
               " to eliminate shift:\n  IN: " << *Op0 << "\n  SH: " << I <<"\n");
 
     return ReplaceInstUsesWith(I,
-                 GetShiftedValue(Op0, COp1->getZExtValue(), isLeftShift, *this));
+                 GetShiftedValue(Op0, Op1->getZExtValue(), isLeftShift, *this));
   }
 
 
@@ -343,7 +333,7 @@ Instruction *InstCombiner::FoldShiftByCo
   // shl i32 X, 32 = 0 and srl i8 Y, 9 = 0, ... just don't eliminate
   // a signed shift.
   //
-  if (COp1->uge(TypeBits)) {
+  if (Op1->uge(TypeBits)) {
     if (I.getOpcode() != Instruction::AShr)
       return ReplaceInstUsesWith(I, Constant::getNullValue(Op0->getType()));
     // ashr i32 X, 32 --> ashr i32 X, 31
@@ -356,7 +346,7 @@ Instruction *InstCombiner::FoldShiftByCo
     if (BO->getOpcode() == Instruction::Mul && isLeftShift)
       if (Constant *BOOp = dyn_cast<Constant>(BO->getOperand(1)))
         return BinaryOperator::CreateMul(BO->getOperand(0),
-                                        ConstantExpr::getShl(BOOp, COp1));
+                                        ConstantExpr::getShl(BOOp, Op1));
 
   // Try to fold constant and into select arguments.
   if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
@@ -377,7 +367,7 @@ Instruction *InstCombiner::FoldShiftByCo
     if (TrOp && I.isLogicalShift() && TrOp->isShift() &&
         isa<ConstantInt>(TrOp->getOperand(1))) {
       // Okay, we'll do this xform.  Make the shift of shift.
-      Constant *ShAmt = ConstantExpr::getZExt(COp1, TrOp->getType());
+      Constant *ShAmt = ConstantExpr::getZExt(Op1, TrOp->getType());
       // (shift2 (shift1 & 0x00FF), c2)
       Value *NSh = Builder->CreateBinOp(I.getOpcode(), TrOp, ShAmt,I.getName());
 
@@ -394,10 +384,10 @@ Instruction *InstCombiner::FoldShiftByCo
       // shift.  We know that it is a logical shift by a constant, so adjust the
       // mask as appropriate.
       if (I.getOpcode() == Instruction::Shl)
-        MaskV <<= COp1->getZExtValue();
+        MaskV <<= Op1->getZExtValue();
       else {
         assert(I.getOpcode() == Instruction::LShr && "Unknown logical shift");
-        MaskV = MaskV.lshr(COp1->getZExtValue());
+        MaskV = MaskV.lshr(Op1->getZExtValue());
       }
 
       // shift1 & 0x00FF
@@ -431,7 +421,7 @@ Instruction *InstCombiner::FoldShiftByCo
           // (X + (Y << C))
           Value *X = Builder->CreateBinOp(Op0BO->getOpcode(), YS, V1,
                                           Op0BO->getOperand(1)->getName());
-          uint32_t Op1Val = COp1->getLimitedValue(TypeBits);
+          uint32_t Op1Val = Op1->getLimitedValue(TypeBits);
           return BinaryOperator::CreateAnd(X, ConstantInt::get(I.getContext(),
                      APInt::getHighBitsSet(TypeBits, TypeBits-Op1Val)));
         }
@@ -463,7 +453,7 @@ Instruction *InstCombiner::FoldShiftByCo
           // (X + (Y << C))
           Value *X = Builder->CreateBinOp(Op0BO->getOpcode(), V1, YS,
                                           Op0BO->getOperand(0)->getName());
-          uint32_t Op1Val = COp1->getLimitedValue(TypeBits);
+          uint32_t Op1Val = Op1->getLimitedValue(TypeBits);
           return BinaryOperator::CreateAnd(X, ConstantInt::get(I.getContext(),
                      APInt::getHighBitsSet(TypeBits, TypeBits-Op1Val)));
         }
@@ -551,7 +541,7 @@ Instruction *InstCombiner::FoldShiftByCo
 
     ConstantInt *ShiftAmt1C = cast<ConstantInt>(ShiftOp->getOperand(1));
     uint32_t ShiftAmt1 = ShiftAmt1C->getLimitedValue(TypeBits);
-    uint32_t ShiftAmt2 = COp1->getLimitedValue(TypeBits);
+    uint32_t ShiftAmt2 = Op1->getLimitedValue(TypeBits);
     assert(ShiftAmt2 != 0 && "Should have been simplified earlier");
     if (ShiftAmt1 == 0) return 0;  // Will be simplified in the future.
     Value *X = ShiftOp->getOperand(0);

Modified: llvm/trunk/test/Transforms/InstCombine/shift.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/shift.ll?rev=206153&r1=206152&r2=206153&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/shift.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/shift.ll Mon Apr 14 02:02:57 2014
@@ -36,52 +36,17 @@ define i32 @test4(i8 %A) {
 define i32 @test5(i32 %A) {
 ; CHECK-LABEL: @test5(
 ; CHECK: ret i32 undef
-        %B = lshr i32 %A, 32  ;; shift all bits out
+        %B = lshr i32 %A, 32  ;; shift all bits out 
         ret i32 %B
 }
 
-define <4 x i32> @test5_splat_vector(<4 x i32> %A) {
-; CHECK-LABEL: @test5_splat_vector(
-; CHECK: ret <4 x i32> undef
-  %B = lshr <4 x i32> %A, <i32 32, i32 32, i32 32, i32 32>     ;; shift all bits out
-  ret <4 x i32> %B
-}
-
-define <4 x i32> @test5_zero_vector(<4 x i32> %A) {
-; CHECK-LABEL: @test5_zero_vector(
-; CHECK-NEXT: ret <4 x i32> %A
-  %B = lshr <4 x i32> %A, zeroinitializer
-  ret <4 x i32> %B
-}
-
-define <4 x i32> @test5_non_splat_vector(<4 x i32> %A) {
-; CHECK-LABEL: @test5_non_splat_vector(
-; CHECK-NOT: ret <4 x i32> undef
-  %B = shl <4 x i32> %A, <i32 32, i32 1, i32 2, i32 3>
-  ret <4 x i32> %B
-}
-
 define i32 @test5a(i32 %A) {
 ; CHECK-LABEL: @test5a(
 ; CHECK: ret i32 undef
-        %B = shl i32 %A, 32     ;; shift all bits out
+        %B = shl i32 %A, 32     ;; shift all bits out 
         ret i32 %B
 }
 
-define <4 x i32> @test5a_splat_vector(<4 x i32> %A) {
-; CHECK-LABEL: @test5a_splat_vector(
-; CHECK: ret <4 x i32> undef
-  %B = shl <4 x i32> %A, <i32 32, i32 32, i32 32, i32 32>     ;; shift all bits out
-  ret <4 x i32> %B
-}
-
-define <4 x i32> @test5a_non_splat_vector(<4 x i32> %A) {
-; CHECK-LABEL: @test5a_non_splat_vector(
-; CHECK-NOT: ret <4 x i32> undef
-  %B = shl <4 x i32> %A, <i32 32, i32 1, i32 2, i32 3>
-  ret <4 x i32> %B
-}
-
 define i32 @test5b() {
 ; CHECK-LABEL: @test5b(
 ; CHECK: ret i32 -1
@@ -117,7 +82,7 @@ define i32 @test6a(i32 %A) {
 define i32 @test7(i8 %A) {
 ; CHECK-LABEL: @test7(
 ; CHECK-NEXT: ret i32 -1
-        %shift.upgrd.3 = zext i8 %A to i32
+        %shift.upgrd.3 = zext i8 %A to i32 
         %B = ashr i32 -1, %shift.upgrd.3  ;; Always equal to -1
         ret i32 %B
 }
@@ -267,7 +232,7 @@ define i1 @test16(i32 %X) {
 ; CHECK-NEXT: and i32 %X, 16
 ; CHECK-NEXT: icmp ne i32
 ; CHECK-NEXT: ret i1
-        %tmp.3 = ashr i32 %X, 4
+        %tmp.3 = ashr i32 %X, 4 
         %tmp.6 = and i32 %tmp.3, 1
         %tmp.7 = icmp ne i32 %tmp.6, 0
         ret i1 %tmp.7
@@ -400,12 +365,12 @@ define i1 @test27(i32 %x) nounwind {
   %z = trunc i32 %y to i1
   ret i1 %z
 }
-
+ 
 define i8 @test28(i8 %x) {
 entry:
 ; CHECK-LABEL: @test28(
 ; CHECK:     icmp slt i8 %x, 0
-; CHECK-NEXT:     br i1
+; CHECK-NEXT:     br i1 
 	%tmp1 = lshr i8 %x, 7
 	%cond1 = icmp ne i8 %tmp1, 0
 	br i1 %cond1, label %bb1, label %bb2
@@ -511,7 +476,7 @@ entry:
   %ins = or i128 %tmp23, %tmp27
   %tmp45 = lshr i128 %ins, 64
   ret i128 %tmp45
-
+  
 ; CHECK-LABEL: @test36(
 ; CHECK:  %tmp231 = or i128 %B, %A
 ; CHECK:  %ins = and i128 %tmp231, 18446744073709551615
@@ -527,7 +492,7 @@ entry:
   %tmp45 = lshr i128 %ins, 64
   %tmp46 = trunc i128 %tmp45 to i64
   ret i64 %tmp46
-
+  
 ; CHECK-LABEL: @test37(
 ; CHECK:  %tmp23 = shl nuw nsw i128 %tmp22, 32
 ; CHECK:  %ins = or i128 %tmp23, %A
@@ -815,32 +780,3 @@ bb11:
 bb12:                                             ; preds = %bb11, %bb8, %bb
   ret void
 }
-
-define i32 @test64(i32 %a) {
-; CHECK-LABEL: @test64(
-; CHECK-NEXT: ret i32 undef
-  %b = ashr i32 %a, 32  ; shift all bits out
-  ret i32 %b
-}
-
-define <4 x i32> @test64_splat_vector(<4 x i32> %a) {
-; CHECK-LABEL: @test64_splat_vector
-; CHECK-NEXT: ret <4 x i32> undef
-  %b = ashr <4 x i32> %a, <i32 32, i32 32, i32 32, i32 32>  ; shift all bits out
-  ret <4 x i32> %b
-}
-
-define <4 x i32> @test64_non_splat_vector(<4 x i32> %a) {
-; CHECK-LABEL: @test64_non_splat_vector
-; CHECK-NOT: ret <4 x i32> undef
-  %b = ashr <4 x i32> %a, <i32 32, i32 0, i32 1, i32 2>  ; shift all bits out
-  ret <4 x i32> %b
-}
-
-define <2 x i65> @test_65(<2 x i64> %t) {
-; CHECK-LABEL: @test_65
-  %a = zext <2 x i64> %t to <2 x i65>
-  %sext = shl <2 x i65> %a, <i65 33, i65 33>
-  %b = ashr <2 x i65> %sext, <i65 33, i65 33>
-  ret <2 x i65> %b
-}





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