; RUN: llc < %s -mtriple=nvptx64-nvidia-cuda -mcpu=sm_20 \ ; RUN: | FileCheck %s --check-prefix=PTX ; RUN: opt < %s -mtriple=nvptx64-nvidia-cuda -S -separate-const-offset-from-gep \ ; RUN: -reassociate-geps-verify-no-dead-code -gvn \ ; RUN: | FileCheck %s --check-prefix=IR ; Verifies the SeparateConstOffsetFromGEP pass. ; The following code computes ; *output = array[x][y] + array[x][y+1] + array[x+1][y] + array[x+1][y+1] ; ; We expect SeparateConstOffsetFromGEP to transform it to ; ; float *base = &a[x][y]; ; *output = base[0] + base[1] + base[32] + base[33]; ; ; so the backend can emit PTX that uses fewer virtual registers. @array = internal addrspace(3) global [32 x [32 x float]] zeroinitializer, align 4 define void @sum_of_array(i32 %x, i32 %y, float* nocapture %output) { .preheader: %0 = sext i32 %y to i64 %1 = sext i32 %x to i64 %2 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %0 %3 = addrspacecast float addrspace(3)* %2 to float* %4 = load float, float* %3, align 4 %5 = fadd float %4, 0.000000e+00 %6 = add i32 %y, 1 %7 = sext i32 %6 to i64 %8 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %7 %9 = addrspacecast float addrspace(3)* %8 to float* %10 = load float, float* %9, align 4 %11 = fadd float %5, %10 %12 = add i32 %x, 1 %13 = sext i32 %12 to i64 %14 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %13, i64 %0 %15 = addrspacecast float addrspace(3)* %14 to float* %16 = load float, float* %15, align 4 %17 = fadd float %11, %16 %18 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %13, i64 %7 %19 = addrspacecast float addrspace(3)* %18 to float* %20 = load float, float* %19, align 4 %21 = fadd float %17, %20 store float %21, float* %output, align 4 ret void } ; PTX-LABEL: sum_of_array( ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG:%(rd|r)[0-9]+]]] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+4] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+128] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+132] ; IR-LABEL: @sum_of_array( ; TODO: GVN is unable to preserve the "inbounds" keyword on the first GEP. Need ; some infrastructure changes to enable such optimizations. ; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}} ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 1 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 32 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 33 ; @sum_of_array2 is very similar to @sum_of_array. The only difference is in ; the order of "sext" and "add" when computing the array indices. @sum_of_array ; computes add before sext, e.g., array[sext(x + 1)][sext(y + 1)], while ; @sum_of_array2 computes sext before add, ; e.g., array[sext(x) + 1][sext(y) + 1]. SeparateConstOffsetFromGEP should be ; able to extract constant offsets from both forms. define void @sum_of_array2(i32 %x, i32 %y, float* nocapture %output) { .preheader: %0 = sext i32 %y to i64 %1 = sext i32 %x to i64 %2 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %0 %3 = addrspacecast float addrspace(3)* %2 to float* %4 = load float, float* %3, align 4 %5 = fadd float %4, 0.000000e+00 %6 = add i64 %0, 1 %7 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %6 %8 = addrspacecast float addrspace(3)* %7 to float* %9 = load float, float* %8, align 4 %10 = fadd float %5, %9 %11 = add i64 %1, 1 %12 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %11, i64 %0 %13 = addrspacecast float addrspace(3)* %12 to float* %14 = load float, float* %13, align 4 %15 = fadd float %10, %14 %16 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %11, i64 %6 %17 = addrspacecast float addrspace(3)* %16 to float* %18 = load float, float* %17, align 4 %19 = fadd float %15, %18 store float %19, float* %output, align 4 ret void } ; PTX-LABEL: sum_of_array2( ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG:%(rd|r)[0-9]+]]] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+4] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+128] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+132] ; IR-LABEL: @sum_of_array2( ; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}} ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 1 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 32 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 33 ; This function loads ; array[zext(x)][zext(y)] ; array[zext(x)][zext(y +nuw 1)] ; array[zext(x +nuw 1)][zext(y)] ; array[zext(x +nuw 1)][zext(y +nuw 1)]. ; ; This function is similar to @sum_of_array, but it ; 1) extends array indices using zext instead of sext; ; 2) annotates the addition with "nuw"; otherwise, zext(x + 1) => zext(x) + 1 ; may be invalid. define void @sum_of_array3(i32 %x, i32 %y, float* nocapture %output) { .preheader: %0 = zext i32 %y to i64 %1 = zext i32 %x to i64 %2 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %0 %3 = addrspacecast float addrspace(3)* %2 to float* %4 = load float, float* %3, align 4 %5 = fadd float %4, 0.000000e+00 %6 = add nuw i32 %y, 1 %7 = zext i32 %6 to i64 %8 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %7 %9 = addrspacecast float addrspace(3)* %8 to float* %10 = load float, float* %9, align 4 %11 = fadd float %5, %10 %12 = add nuw i32 %x, 1 %13 = zext i32 %12 to i64 %14 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %13, i64 %0 %15 = addrspacecast float addrspace(3)* %14 to float* %16 = load float, float* %15, align 4 %17 = fadd float %11, %16 %18 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %13, i64 %7 %19 = addrspacecast float addrspace(3)* %18 to float* %20 = load float, float* %19, align 4 %21 = fadd float %17, %20 store float %21, float* %output, align 4 ret void } ; PTX-LABEL: sum_of_array3( ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG:%(rd|r)[0-9]+]]] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+4] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+128] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+132] ; IR-LABEL: @sum_of_array3( ; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}} ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 1 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 32 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 33 ; This function loads ; array[zext(x)][zext(y)] ; array[zext(x)][zext(y)] ; array[zext(x) + 1][zext(y) + 1] ; array[zext(x) + 1][zext(y) + 1]. ; ; We expect the generated code to reuse the computation of ; &array[zext(x)][zext(y)]. See the expected IR and PTX for details. define void @sum_of_array4(i32 %x, i32 %y, float* nocapture %output) { .preheader: %0 = zext i32 %y to i64 %1 = zext i32 %x to i64 %2 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %0 %3 = addrspacecast float addrspace(3)* %2 to float* %4 = load float, float* %3, align 4 %5 = fadd float %4, 0.000000e+00 %6 = add i64 %0, 1 %7 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %1, i64 %6 %8 = addrspacecast float addrspace(3)* %7 to float* %9 = load float, float* %8, align 4 %10 = fadd float %5, %9 %11 = add i64 %1, 1 %12 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %11, i64 %0 %13 = addrspacecast float addrspace(3)* %12 to float* %14 = load float, float* %13, align 4 %15 = fadd float %10, %14 %16 = getelementptr inbounds [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %11, i64 %6 %17 = addrspacecast float addrspace(3)* %16 to float* %18 = load float, float* %17, align 4 %19 = fadd float %15, %18 store float %19, float* %output, align 4 ret void } ; PTX-LABEL: sum_of_array4( ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG:%(rd|r)[0-9]+]]] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+4] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+128] ; PTX-DAG: ld.shared.f32 {{%f[0-9]+}}, [[[BASE_REG]]+132] ; IR-LABEL: @sum_of_array4( ; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr [32 x [32 x float]], [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}} ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 1 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 32 ; IR: getelementptr inbounds float, float addrspace(3)* [[BASE_PTR]], i64 33 ; The source code is: ; p0 = &input[sext(x + y)]; ; p1 = &input[sext(x + (y + 5))]; ; ; Without reuniting extensions, SeparateConstOffsetFromGEP would emit ; p0 = &input[sext(x + y)]; ; t1 = &input[sext(x) + sext(y)]; ; p1 = &t1[5]; ; ; With reuniting extensions, it merges p0 and t1 and thus emits ; p0 = &input[sext(x + y)]; ; p1 = &p0[5]; define void @reunion(i32 %x, i32 %y, float* %input) { ; IR-LABEL: @reunion( ; PTX-LABEL: reunion( entry: %xy = add nsw i32 %x, %y %0 = sext i32 %xy to i64 %p0 = getelementptr inbounds float, float* %input, i64 %0 %v0 = load float, float* %p0, align 4 ; PTX: ld.f32 %f{{[0-9]+}}, [[[p0:%rd[0-9]+]]] call void @use(float %v0) %y5 = add nsw i32 %y, 5 %xy5 = add nsw i32 %x, %y5 %1 = sext i32 %xy5 to i64 %p1 = getelementptr inbounds float, float* %input, i64 %1 ; IR: getelementptr inbounds float, float* %p0, i64 5 %v1 = load float, float* %p1, align 4 ; PTX: ld.f32 %f{{[0-9]+}}, [[[p0]]+20] call void @use(float %v1) ret void } declare void @use(float)