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; RUN: llc < %s -march=nvptx64 -mcpu=sm_20 | FileCheck %s --check-prefix=PTX
; RUN: opt < %s -S -separate-const-offset-from-gep -gvn -dce | 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.
target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64"
target triple = "nvptx64-unknown-unknown"
@array = internal addrspace(3) constant [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]] addrspace(3)* @array, i64 0, i64 %1, i64 %0
%3 = addrspacecast float addrspace(3)* %2 to float*
%4 = load 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]] addrspace(3)* @array, i64 0, i64 %1, i64 %7
%9 = addrspacecast float addrspace(3)* %8 to float*
%10 = load 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]] addrspace(3)* @array, i64 0, i64 %13, i64 %0
%15 = addrspacecast float addrspace(3)* %14 to float*
%16 = load float* %15, align 4
%17 = fadd float %11, %16
%18 = getelementptr inbounds [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* %19, align 4
%21 = fadd float %17, %20
store float %21, float* %output, align 4
ret void
}
; PTX-LABEL: sum_of_array(
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG:%(rl|r)[0-9]+]]{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+4{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+128{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+132{{\]}}
; IR-LABEL: @sum_of_array(
; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr inbounds [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}}
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 1
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 32
; IR: getelementptr 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]] addrspace(3)* @array, i64 0, i64 %1, i64 %0
%3 = addrspacecast float addrspace(3)* %2 to float*
%4 = load float* %3, align 4
%5 = fadd float %4, 0.000000e+00
%6 = add i64 %0, 1
%7 = getelementptr inbounds [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* %8, align 4
%10 = fadd float %5, %9
%11 = add i64 %1, 1
%12 = getelementptr inbounds [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* %13, align 4
%15 = fadd float %10, %14
%16 = getelementptr inbounds [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* %17, align 4
%19 = fadd float %15, %18
store float %19, float* %output, align 4
ret void
}
; PTX-LABEL: sum_of_array2(
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG:%(rl|r)[0-9]+]]{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+4{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+128{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+132{{\]}}
; IR-LABEL: @sum_of_array2(
; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr inbounds [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}}
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 1
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 32
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 33
; Similar to @sum_of_array3, but extends array indices using zext instead of
; sext. e.g., array[zext(x + 1)][zext(y + 1)].
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]] addrspace(3)* @array, i64 0, i64 %1, i64 %0
%3 = addrspacecast float addrspace(3)* %2 to float*
%4 = load float* %3, align 4
%5 = fadd float %4, 0.000000e+00
%6 = add i32 %y, 1
%7 = zext i32 %6 to i64
%8 = getelementptr inbounds [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* %9, align 4
%11 = fadd float %5, %10
%12 = add i32 %x, 1
%13 = zext i32 %12 to i64
%14 = getelementptr inbounds [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* %15, align 4
%17 = fadd float %11, %16
%18 = getelementptr inbounds [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* %19, align 4
%21 = fadd float %17, %20
store float %21, float* %output, align 4
ret void
}
; PTX-LABEL: sum_of_array3(
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG:%(rl|r)[0-9]+]]{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+4{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+128{{\]}}
; PTX: ld.shared.f32 {{%f[0-9]+}}, {{\[}}[[BASE_REG]]+132{{\]}}
; IR-LABEL: @sum_of_array3(
; IR: [[BASE_PTR:%[a-zA-Z0-9]+]] = getelementptr inbounds [32 x [32 x float]] addrspace(3)* @array, i64 0, i64 %{{[a-zA-Z0-9]+}}, i64 %{{[a-zA-Z0-9]+}}
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 1
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 32
; IR: getelementptr float addrspace(3)* [[BASE_PTR]], i64 33
|
