diff options
| -rw-r--r-- | llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp | 9 | ||||
| -rw-r--r-- | llvm/test/Transforms/LoopVectorize/ARM/gather-cost.ll | 88 |
2 files changed, 97 insertions, 0 deletions
diff --git a/llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp b/llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp index 79f56a4b68c..5cc64ded465 100644 --- a/llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp +++ b/llvm/lib/Target/ARM/ARMTargetTransformInfo.cpp @@ -426,6 +426,15 @@ unsigned ARMTTI::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, } unsigned ARMTTI::getAddressComputationCost(Type *Ty, bool IsComplex) const { + // Address computations in vectorized code with non-consecutive addresses will + // likely result in more instructions compared to scalar code where the + // computation can more often be merged into the index mode. The resulting + // extra micro-ops can significantly decrease throughput. + unsigned NumVectorInstToHideOverhead = 10; + + if (Ty->isVectorTy() && IsComplex) + return NumVectorInstToHideOverhead; + // In many cases the address computation is not merged into the instruction // addressing mode. return 1; diff --git a/llvm/test/Transforms/LoopVectorize/ARM/gather-cost.ll b/llvm/test/Transforms/LoopVectorize/ARM/gather-cost.ll new file mode 100644 index 00000000000..239a28fa6c7 --- /dev/null +++ b/llvm/test/Transforms/LoopVectorize/ARM/gather-cost.ll @@ -0,0 +1,88 @@ +; RUN: opt -loop-vectorize -mtriple=thumbv7s-apple-ios6.0.0 -S < %s | FileCheck %s + +target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:32:64-v128:32:128-a0:0:32-n32-S32" + +@kernel = global [512 x float] zeroinitializer, align 4 +@kernel2 = global [512 x float] zeroinitializer, align 4 +@kernel3 = global [512 x float] zeroinitializer, align 4 +@kernel4 = global [512 x float] zeroinitializer, align 4 +@src_data = global [1536 x float] zeroinitializer, align 4 +@r_ = global i8 0, align 4 +@g_ = global i8 0, align 4 +@b_ = global i8 0, align 4 + +; We don't want to vectorize most loops containing gathers because they are +; expensive. This function represents a point where vectorization starts to +; become beneficial. +; Make sure we are conservative and don't vectorize it. +; CHECK-NOT: <2 x float> +; CHECK-NOT: <4 x float> + +define void @_Z4testmm(i32 %size, i32 %offset) { +entry: + %cmp53 = icmp eq i32 %size, 0 + br i1 %cmp53, label %for.end, label %for.body.lr.ph + +for.body.lr.ph: + br label %for.body + +for.body: + %r.057 = phi float [ 0.000000e+00, %for.body.lr.ph ], [ %add10, %for.body ] + %g.056 = phi float [ 0.000000e+00, %for.body.lr.ph ], [ %add20, %for.body ] + %v.055 = phi i32 [ 0, %for.body.lr.ph ], [ %inc, %for.body ] + %b.054 = phi float [ 0.000000e+00, %for.body.lr.ph ], [ %add30, %for.body ] + %add = add i32 %v.055, %offset + %mul = mul i32 %add, 3 + %arrayidx = getelementptr inbounds [1536 x float]* @src_data, i32 0, i32 %mul + %0 = load float* %arrayidx, align 4 + %arrayidx2 = getelementptr inbounds [512 x float]* @kernel, i32 0, i32 %v.055 + %1 = load float* %arrayidx2, align 4 + %mul3 = fmul fast float %0, %1 + %arrayidx4 = getelementptr inbounds [512 x float]* @kernel2, i32 0, i32 %v.055 + %2 = load float* %arrayidx4, align 4 + %mul5 = fmul fast float %mul3, %2 + %arrayidx6 = getelementptr inbounds [512 x float]* @kernel3, i32 0, i32 %v.055 + %3 = load float* %arrayidx6, align 4 + %mul7 = fmul fast float %mul5, %3 + %arrayidx8 = getelementptr inbounds [512 x float]* @kernel4, i32 0, i32 %v.055 + %4 = load float* %arrayidx8, align 4 + %mul9 = fmul fast float %mul7, %4 + %add10 = fadd fast float %r.057, %mul9 + %arrayidx.sum = add i32 %mul, 1 + %arrayidx11 = getelementptr inbounds [1536 x float]* @src_data, i32 0, i32 %arrayidx.sum + %5 = load float* %arrayidx11, align 4 + %mul13 = fmul fast float %1, %5 + %mul15 = fmul fast float %2, %mul13 + %mul17 = fmul fast float %3, %mul15 + %mul19 = fmul fast float %4, %mul17 + %add20 = fadd fast float %g.056, %mul19 + %arrayidx.sum52 = add i32 %mul, 2 + %arrayidx21 = getelementptr inbounds [1536 x float]* @src_data, i32 0, i32 %arrayidx.sum52 + %6 = load float* %arrayidx21, align 4 + %mul23 = fmul fast float %1, %6 + %mul25 = fmul fast float %2, %mul23 + %mul27 = fmul fast float %3, %mul25 + %mul29 = fmul fast float %4, %mul27 + %add30 = fadd fast float %b.054, %mul29 + %inc = add i32 %v.055, 1 + %exitcond = icmp ne i32 %inc, %size + br i1 %exitcond, label %for.body, label %for.cond.for.end_crit_edge + +for.cond.for.end_crit_edge: + %add30.lcssa = phi float [ %add30, %for.body ] + %add20.lcssa = phi float [ %add20, %for.body ] + %add10.lcssa = phi float [ %add10, %for.body ] + %phitmp = fptoui float %add10.lcssa to i8 + %phitmp60 = fptoui float %add20.lcssa to i8 + %phitmp61 = fptoui float %add30.lcssa to i8 + br label %for.end + +for.end: + %r.0.lcssa = phi i8 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ] + %g.0.lcssa = phi i8 [ %phitmp60, %for.cond.for.end_crit_edge ], [ 0, %entry ] + %b.0.lcssa = phi i8 [ %phitmp61, %for.cond.for.end_crit_edge ], [ 0, %entry ] + store i8 %r.0.lcssa, i8* @r_, align 4 + store i8 %g.0.lcssa, i8* @g_, align 4 + store i8 %b.0.lcssa, i8* @b_, align 4 + ret void +} |
