Index: llvm/trunk/lib/Analysis/InlineCost.cpp =================================================================== --- llvm/trunk/lib/Analysis/InlineCost.cpp +++ llvm/trunk/lib/Analysis/InlineCost.cpp @@ -241,6 +241,7 @@ bool visitCallSite(CallSite CS); bool visitReturnInst(ReturnInst &RI); bool visitBranchInst(BranchInst &BI); + bool visitSelectInst(SelectInst &SI); bool visitSwitchInst(SwitchInst &SI); bool visitIndirectBrInst(IndirectBrInst &IBI); bool visitResumeInst(ResumeInst &RI); @@ -1177,6 +1178,87 @@ SimplifiedValues.lookup(BI.getCondition())); } +bool CallAnalyzer::visitSelectInst(SelectInst &SI) { + bool CheckSROA = SI.getType()->isPointerTy(); + Value *TrueVal = SI.getTrueValue(); + Value *FalseVal = SI.getFalseValue(); + + Constant *TrueC = dyn_cast(TrueVal); + if (!TrueC) + TrueC = SimplifiedValues.lookup(TrueVal); + Constant *FalseC = dyn_cast(FalseVal); + if (!FalseC) + FalseC = SimplifiedValues.lookup(FalseVal); + Constant *CondC = + dyn_cast_or_null(SimplifiedValues.lookup(SI.getCondition())); + + if (!CondC) { + // Select C, X, X => X + if (TrueC == FalseC && TrueC) { + SimplifiedValues[&SI] = TrueC; + return true; + } + + if (!CheckSROA) + return Base::visitSelectInst(SI); + + std::pair TrueBaseAndOffset = + ConstantOffsetPtrs.lookup(TrueVal); + std::pair FalseBaseAndOffset = + ConstantOffsetPtrs.lookup(FalseVal); + if (TrueBaseAndOffset == FalseBaseAndOffset && TrueBaseAndOffset.first) { + ConstantOffsetPtrs[&SI] = TrueBaseAndOffset; + + Value *SROAArg; + DenseMap::iterator CostIt; + if (lookupSROAArgAndCost(TrueVal, SROAArg, CostIt)) + SROAArgValues[&SI] = SROAArg; + return true; + } + + return Base::visitSelectInst(SI); + } + + // Select condition is a constant. + Value *SelectedV = CondC->isAllOnesValue() + ? TrueVal + : (CondC->isNullValue()) ? FalseVal : nullptr; + if (!SelectedV) { + // Condition is a vector constant that is not all 1s or all 0s. If all + // operands are constants, ConstantExpr::getSelect() can handle the cases + // such as select vectors. + if (TrueC && FalseC) { + if (auto *C = ConstantExpr::getSelect(CondC, TrueC, FalseC)) { + SimplifiedValues[&SI] = C; + return true; + } + } + return Base::visitSelectInst(SI); + } + + // Condition is either all 1s or all 0s. SI can be simplified. + if (Constant *SelectedC = dyn_cast(SelectedV)) { + SimplifiedValues[&SI] = SelectedC; + return true; + } + + if (!CheckSROA) + return true; + + std::pair BaseAndOffset = + ConstantOffsetPtrs.lookup(SelectedV); + if (BaseAndOffset.first) { + ConstantOffsetPtrs[&SI] = BaseAndOffset; + + Value *SROAArg; + DenseMap::iterator CostIt; + if (lookupSROAArgAndCost(SelectedV, SROAArg, CostIt)) + SROAArgValues[&SI] = SROAArg; + } + + return true; +} + bool CallAnalyzer::visitSwitchInst(SwitchInst &SI) { // We model unconditional switches as free, see the comments on handling // branches. Index: llvm/trunk/test/Transforms/Inline/AArch64/select.ll =================================================================== --- llvm/trunk/test/Transforms/Inline/AArch64/select.ll +++ llvm/trunk/test/Transforms/Inline/AArch64/select.ll @@ -0,0 +1,251 @@ +; RUN: opt -inline -mtriple=aarch64--linux-gnu -S -o - < %s -inline-threshold=0 | FileCheck %s + +target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128" +target triple = "aarch64--linux-gnu" + +declare void @pad() +@glbl = external global i32 + +define i32 @outer1(i1 %cond) { +; CHECK-LABEL: @outer1( +; CHECK-NOT: call i32 @inner1 + %C = call i32 @inner1(i1 %cond, i32 1) + ret i32 %C +} + +define i32 @inner1(i1 %cond, i32 %val) { + %select = select i1 %cond, i32 1, i32 %val ; Simplified to 1 + call void @pad() + store i32 0, i32* @glbl + ret i32 %select ; Simplifies to ret i32 1 +} + + +define i32 @outer2(i32 %val) { +; CHECK-LABEL: @outer2( +; CHECK-NOT: call i32 @inner2 + %C = call i32 @inner2(i1 true, i32 %val) + ret i32 %C +} + +define i32 @inner2(i1 %cond, i32 %val) { + %select = select i1 %cond, i32 1, i32 %val ; Simplifies to 1 + call void @pad() + store i32 0, i32* @glbl + ret i32 %select ; Simplifies to ret i32 1 +} + + +define i32 @outer3(i32 %val) { +; CHECK-LABEL: @outer3( +; CHECK-NOT: call i32 @inner3 + %C = call i32 @inner3(i1 false, i32 %val) + ret i32 %C +} + +define i32 @inner3(i1 %cond, i32 %val) { + %select = select i1 %cond, i32 %val, i32 -1 ; Simplifies to -1 + call void @pad() + store i32 0, i32* @glbl + ret i32 %select ; Simplifies to ret i32 -1 +} + + +define i32 @outer4() { +; CHECK-LABEL: @outer4( +; CHECK-NOT: call i32 @inner4 + %C = call i32 @inner4(i1 true, i32 1, i32 -1) + ret i32 %C +} + +define i32 @inner4(i1 %cond, i32 %val1, i32 %val2) { + %select = select i1 %cond, i32 %val1, i32 %val2 ; Simplifies to 1 + call void @pad() + store i32 0, i32* @glbl + store i32 1, i32* @glbl + ret i32 %select ; Simplifies to ret i32 1 +} + + +define i1 @outer5() { +; CHECK-LABEL: @outer5( +; CHECK-NOT: call i1 @inner5 + %C = call i1 @inner5(i1 true, i1 true, i1 false) + ret i1 %C +} + +declare void @dead() + +define i1 @inner5(i1 %cond, i1 %val1, i1 %val2) { + %select = select i1 %cond, i1 %val1, i1 %val2 ; Simplifies to true + br i1 %select, label %exit, label %isfalse ; Simplifies to br label %end + +isfalse: ; This block is unreachable once inlined + call void @dead() + br label %exit + +exit: + store i32 0, i32* @glbl + ret i1 %select ; Simplifies to ret i1 true +} + + +define i32 @outer6(i1 %cond) { +; CHECK-LABEL: @outer6( +; CHECK-NOT: call i32 @inner6 + %A = alloca i32 + %C = call i32 @inner6(i1 %cond, i32* %A) + ret i32 %C +} + +define i32 @inner6(i1 %cond, i32* %ptr) { + %G1 = getelementptr inbounds i32, i32* %ptr, i32 1 + %G2 = getelementptr inbounds i32, i32* %G1, i32 1 + %G3 = getelementptr inbounds i32, i32* %ptr, i32 2 + %select = select i1 %cond, i32* %G2, i32* %G3 ; Simplified to %A[2] + %load = load i32, i32* %select ; SROA'ed + call void @pad() + ret i32 %load ; Simplified +} + + +define i32 @outer7(i32* %ptr) { +; CHECK-LABEL: @outer7( +; CHECK-NOT: call i32 @inner7 + %A = alloca i32 + %C = call i32 @inner7(i1 true, i32* %A, i32* %ptr) + ret i32 %C +} + +define i32 @inner7(i1 %cond, i32* %p1, i32* %p2) { + %select = select i1 %cond, i32* %p1, i32* %p2 ; Simplifies to %A + %load = load i32, i32* %select ; SROA'ed + call void @pad() + store i32 0, i32* @glbl + ret i32 %load ; Simplified +} + + +define i32 @outer8(i32* %ptr) { +; CHECK-LABEL: @outer8( +; CHECK-NOT: call i32 @inner8 + %A = alloca i32 + %C = call i32 @inner8(i1 false, i32* %ptr, i32* %A) + ret i32 %C +} + +define i32 @inner8(i1 %cond, i32* %p1, i32* %p2) { + %select = select i1 %cond, i32* %p1, i32* %p2 ; Simplifies to %A + %load = load i32, i32* %select ; SROA'ed + call void @pad() + store i32 0, i32* @glbl + ret i32 %load ; Simplified +} + + +define <2 x i32> @outer9(<2 x i32> %val) { +; CHECK-LABEL: @outer9( +; CHECK-NOT: call <2 x i32> @inner9 + %C = call <2 x i32> @inner9(<2 x i1> , <2 x i32> %val) + ret <2 x i32> %C +} + +define <2 x i32> @inner9(<2 x i1> %cond, <2 x i32> %val) { + %select = select <2 x i1> %cond, <2 x i32> , <2 x i32> %val ; Simplifies to <1, 1> + call void @pad() + store i32 0, i32* @glbl + ret <2 x i32> %select ; Simplifies to ret <2 x i32> <1, 1> +} + + +define <2 x i32> @outer10(<2 x i32> %val) { +; CHECK-LABEL: @outer10( +; CHECK-NOT: call <2 x i32> @inner10 + %C = call <2 x i32> @inner10(<2 x i1> , <2 x i32> %val) + ret <2 x i32> %C +} + +define <2 x i32> @inner10(<2 x i1> %cond, <2 x i32> %val) { + %select = select <2 x i1> %cond, < 2 x i32> %val, <2 x i32> ; Simplifies to <-1, -1> + call void @pad() + store i32 0, i32* @glbl + ret <2 x i32> %select ; Simplifies to ret <2 x i32> <-1, -1> +} + + +define <2 x i32> @outer11() { +; CHECK-LABEL: @outer11( +; CHECK-NOT: call <2 x i32> @inner11 + %C = call <2 x i32> @inner11(<2 x i1> ) + ret <2 x i32> %C +} + +define <2 x i32> @inner11(<2 x i1> %cond) { + %select = select <2 x i1> %cond, <2 x i32> , < 2 x i32> ; Simplifies to <1, -1> + call void @pad() + ret <2 x i32> %select ; Simplifies to ret <2 x i32> <1, -1> +} + + +define i1 @outer12(i32* %ptr) { +; CHECK-LABEL: @outer12( +; CHECK-NOT: call i1 @inner12 + %C = call i1 @inner12(i1 true, i32* @glbl, i32* %ptr) + ret i1 %C +} + +define i1 @inner12(i1 %cond, i32* %ptr1, i32* %ptr2) { + %select = select i1 %cond, i32* %ptr1, i32* %ptr2 ; Simplified to @glbl + %cmp = icmp eq i32* %select, @glbl ; Simplified to true + call void @pad() + store i32 0, i32* @glbl + ret i1 %cmp ; Simplifies to ret i1 true +} + + +define <2 x i32> @outer13(<2 x i32> %val1, <2 x i32> %val2) { +; CHECK-LABEL: @outer13( +; CHECK: call <2 x i32> @inner13 + %C = call <2 x i32> @inner13(<2 x i1> , <2 x i32> %val1, <2 x i32> %val2) + ret <2 x i32> %C +} + +define <2 x i32> @inner13(<2 x i1> %cond, <2 x i32> %val1, < 2 x i32> %val2) { + %select = select <2 x i1> %cond, <2 x i32> %val1, < 2 x i32> %val2 ; Cannot be Simplified + call void @pad() + store i32 0, i32* @glbl + store i32 1, i32* @glbl + ret <2 x i32> %select ; Simplified +} + + +define i32 @outer14(i32 %val1, i32 %val2) { +; CHECK-LABEL: @outer14( +; CHECK-NOT: call i32 @inner14 + %C = call i32 @inner14(i1 true, i32 %val1, i32 %val2) + ret i32 %C +} + +define i32 @inner14(i1 %cond, i32 %val1, i32 %val2) { + %select = select i1 %cond, i32 %val1, i32 %val2 ; Simplified to %val1 + call void @pad() + store i32 0, i32* @glbl + store i32 1, i32* @glbl + ret i32 %select ; Simplifies to ret i32 %val1 +} + + +define i32 @outer15(i32 %val1, i32 %val2) { +; CHECK-LABEL: @outer15( +; CHECK-NOT: call i32 @inner15 + %C = call i32 @inner15(i1 false, i32 %val1, i32 %val2) + ret i32 %C +} + +define i32 @inner15(i1 %cond, i32 %val1, i32 %val2) { + %select = select i1 %cond, i32 %val1, i32 %val2 ; Simplified to %val2 + call void @pad() + store i32 0, i32* @glbl + store i32 1, i32* @glbl + ret i32 %select ; Simplifies to ret i32 %val2 +}