|  |  | 
|  | ; RUN: opt < %s -instcombine -S | not grep fpext | 
|  | @X = external global float | 
|  | @Y = external global float | 
|  |  | 
|  | define void @test() nounwind  { | 
|  | entry: | 
|  | %tmp = load float, float* @X, align 4		; <float> [#uses=1] | 
|  | %tmp1 = fpext float %tmp to double		; <double> [#uses=1] | 
|  | %tmp3 = fadd double %tmp1, 0.000000e+00		; <double> [#uses=1] | 
|  | %tmp34 = fptrunc double %tmp3 to float		; <float> [#uses=1] | 
|  | store float %tmp34, float* @X, align 4 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @test2() nounwind  { | 
|  | entry: | 
|  | %tmp = load float, float* @X, align 4		; <float> [#uses=1] | 
|  | %tmp1 = fpext float %tmp to double		; <double> [#uses=1] | 
|  | %tmp2 = load float, float* @Y, align 4		; <float> [#uses=1] | 
|  | %tmp23 = fpext float %tmp2 to double		; <double> [#uses=1] | 
|  | %tmp5 = fmul double %tmp1, %tmp23		; <double> [#uses=1] | 
|  | %tmp56 = fptrunc double %tmp5 to float		; <float> [#uses=1] | 
|  | store float %tmp56, float* @X, align 4 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @test3() nounwind  { | 
|  | entry: | 
|  | %tmp = load float, float* @X, align 4		; <float> [#uses=1] | 
|  | %tmp1 = fpext float %tmp to double		; <double> [#uses=1] | 
|  | %tmp2 = load float, float* @Y, align 4		; <float> [#uses=1] | 
|  | %tmp23 = fpext float %tmp2 to double		; <double> [#uses=1] | 
|  | %tmp5 = fdiv double %tmp1, %tmp23		; <double> [#uses=1] | 
|  | %tmp56 = fptrunc double %tmp5 to float		; <float> [#uses=1] | 
|  | store float %tmp56, float* @X, align 4 | 
|  | ret void | 
|  | } | 
|  |  | 
|  | define void @test4() nounwind  { | 
|  | entry: | 
|  | %tmp = load float, float* @X, align 4		; <float> [#uses=1] | 
|  | %tmp1 = fpext float %tmp to double		; <double> [#uses=1] | 
|  | %tmp2 = fsub double -0.000000e+00, %tmp1		; <double> [#uses=1] | 
|  | %tmp34 = fptrunc double %tmp2 to float		; <float> [#uses=1] | 
|  | store float %tmp34, float* @X, align 4 | 
|  | ret void | 
|  | } |