1; RUN: opt < %s -instcombine -S | grep "insertelement <4 x float> undef" 2 3; Instcombine should be able to prove that none of the 4; insertelement's first operand's elements are needed. 5 6define internal void @""(i8*) { 7; <label>:1 8 bitcast i8* %0 to i32* ; <i32*>:2 [#uses=1] 9 load i32, i32* %2, align 1 ; <i32>:3 [#uses=1] 10 getelementptr i8, i8* %0, i32 4 ; <i8*>:4 [#uses=1] 11 bitcast i8* %4 to i32* ; <i32*>:5 [#uses=1] 12 load i32, i32* %5, align 1 ; <i32>:6 [#uses=1] 13 br label %7 14 15; <label>:7 ; preds = %9, %1 16 %.01 = phi <4 x float> [ undef, %1 ], [ %12, %9 ] ; <<4 x float>> [#uses=1] 17 %.0 = phi i32 [ %3, %1 ], [ %15, %9 ] ; <i32> [#uses=3] 18 icmp slt i32 %.0, %6 ; <i1>:8 [#uses=1] 19 br i1 %8, label %9, label %16 20 21; <label>:9 ; preds = %7 22 sitofp i32 %.0 to float ; <float>:10 [#uses=1] 23 insertelement <4 x float> %.01, float %10, i32 0 ; <<4 x float>>:11 [#uses=1] 24 shufflevector <4 x float> %11, <4 x float> undef, <4 x i32> zeroinitializer ; <<4 x float>>:12 [#uses=2] 25 getelementptr i8, i8* %0, i32 48 ; <i8*>:13 [#uses=1] 26 bitcast i8* %13 to <4 x float>* ; <<4 x float>*>:14 [#uses=1] 27 store <4 x float> %12, <4 x float>* %14, align 16 28 add i32 %.0, 2 ; <i32>:15 [#uses=1] 29 br label %7 30 31; <label>:16 ; preds = %7 32 ret void 33} 34