void __attribute__((no, noclone)) set_double_immfp0(double *a) {
  for (int i = 0; i < (1024 / sizeof(double)); i++)
    a[i] = 0x1.fp0;
}


x86 assembly (clang, -O0):
<set_double_immfp0>:
push   %rbp
mov    %rsp,%rbp
mov    %rdi,-0x8(%rbp)
movl   $0x0,-0xc(%rbp)
movslq -0xc(%rbp),%rax
cmp    $0x80,%rax
jae    1142 <set_double_immfp0+0x42>
mov    -0x8(%rbp),%rax
movslq -0xc(%rbp),%rcx
movsd  0xed1(%rip),%xmm0
movsd  %xmm0,(%rax,%rcx,8)
mov    -0xc(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0xc(%rbp)
jmp    110f <set_double_immfp0+0xf>
pop    %rbp
ret

x86 assembly (clang, -O2):
<set_double_immfp0>:
movaps 0xef9(%rip),%xmm0
movups %xmm0,(%rdi)
movups %xmm0,0x10(%rdi)
movups %xmm0,0x20(%rdi)
movups %xmm0,0x30(%rdi)
movups %xmm0,0x40(%rdi)
movups %xmm0,0x50(%rdi)
movups %xmm0,0x60(%rdi)
movups %xmm0,0x70(%rdi)
movups %xmm0,0x80(%rdi)
movups %xmm0,0x90(%rdi)
movups %xmm0,0xa0(%rdi)
movups %xmm0,0xb0(%rdi)
movups %xmm0,0xc0(%rdi)
movups %xmm0,0xd0(%rdi)
movups %xmm0,0xe0(%rdi)
movups %xmm0,0xf0(%rdi)
movups %xmm0,0x100(%rdi)
movups %xmm0,0x110(%rdi)
movups %xmm0,0x120(%rdi)
movups %xmm0,0x130(%rdi)
movups %xmm0,0x140(%rdi)
movups %xmm0,0x150(%rdi)
movups %xmm0,0x160(%rdi)
movups %xmm0,0x170(%rdi)
movups %xmm0,0x180(%rdi)
movups %xmm0,0x190(%rdi)
movups %xmm0,0x1a0(%rdi)
movups %xmm0,0x1b0(%rdi)
movups %xmm0,0x1c0(%rdi)
movups %xmm0,0x1d0(%rdi)
movups %xmm0,0x1e0(%rdi)
movups %xmm0,0x1f0(%rdi)
movups %xmm0,0x200(%rdi)
movups %xmm0,0x210(%rdi)
movups %xmm0,0x220(%rdi)
movups %xmm0,0x230(%rdi)
movups %xmm0,0x240(%rdi)
movups %xmm0,0x250(%rdi)
movups %xmm0,0x260(%rdi)
movups %xmm0,0x270(%rdi)
movups %xmm0,0x280(%rdi)
movups %xmm0,0x290(%rdi)
movups %xmm0,0x2a0(%rdi)
movups %xmm0,0x2b0(%rdi)
movups %xmm0,0x2c0(%rdi)
movups %xmm0,0x2d0(%rdi)
movups %xmm0,0x2e0(%rdi)
movups %xmm0,0x2f0(%rdi)
movups %xmm0,0x300(%rdi)
movups %xmm0,0x310(%rdi)
movups %xmm0,0x320(%rdi)
movups %xmm0,0x330(%rdi)
movups %xmm0,0x340(%rdi)
movups %xmm0,0x350(%rdi)
movups %xmm0,0x360(%rdi)
movups %xmm0,0x370(%rdi)
movups %xmm0,0x380(%rdi)
movups %xmm0,0x390(%rdi)
movups %xmm0,0x3a0(%rdi)
movups %xmm0,0x3b0(%rdi)
movups %xmm0,0x3c0(%rdi)
movups %xmm0,0x3d0(%rdi)
movups %xmm0,0x3e0(%rdi)
movups %xmm0,0x3f0(%rdi)
ret

LLVM IR (-O0):
define void @set_double_immfp0(double* %0) {
%2 = alloca double*
%3 = alloca i32
store double* %0, double** %2
store i32 0, i32* %3
br label %4
4: ; preds = %13, %1
%5 = load i32, i32* %3
%6 = sext i32 %5 to i64
%7 = icmp ult i64 %6, 128
br i1 %7, label %8, label %16
8: ; preds = %4
%9 = load double*, double** %2
%10 = load i32, i32* %3
%11 = sext i32 %10 to i64
%12 = getelementptr inbounds double, double* %9, i64 %11
store double 1.937500e+00, double* %12
br label %13
13: ; preds = %8
%14 = load i32, i32* %3
%15 = add nsw i32 %14, 1
store i32 %15, i32* %3
br label %4
16: ; preds = %4
ret void
}

LLVM IR (-O2):
define void @set_double_immfp0(double* nocapture writeonly %0) {
%2 = bitcast double* %0 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %2
%3 = getelementptr inbounds double, double* %0, i64 2
%4 = bitcast double* %3 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %4
%5 = getelementptr inbounds double, double* %0, i64 4
%6 = bitcast double* %5 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %6
%7 = getelementptr inbounds double, double* %0, i64 6
%8 = bitcast double* %7 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %8
%9 = getelementptr inbounds double, double* %0, i64 8
%10 = bitcast double* %9 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %10
%11 = getelementptr inbounds double, double* %0, i64 10
%12 = bitcast double* %11 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %12
%13 = getelementptr inbounds double, double* %0, i64 12
%14 = bitcast double* %13 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %14
%15 = getelementptr inbounds double, double* %0, i64 14
%16 = bitcast double* %15 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %16
%17 = getelementptr inbounds double, double* %0, i64 16
%18 = bitcast double* %17 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %18
%19 = getelementptr inbounds double, double* %0, i64 18
%20 = bitcast double* %19 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %20
%21 = getelementptr inbounds double, double* %0, i64 20
%22 = bitcast double* %21 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %22
%23 = getelementptr inbounds double, double* %0, i64 22
%24 = bitcast double* %23 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %24
%25 = getelementptr inbounds double, double* %0, i64 24
%26 = bitcast double* %25 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %26
%27 = getelementptr inbounds double, double* %0, i64 26
%28 = bitcast double* %27 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %28
%29 = getelementptr inbounds double, double* %0, i64 28
%30 = bitcast double* %29 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %30
%31 = getelementptr inbounds double, double* %0, i64 30
%32 = bitcast double* %31 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %32
%33 = getelementptr inbounds double, double* %0, i64 32
%34 = bitcast double* %33 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %34
%35 = getelementptr inbounds double, double* %0, i64 34
%36 = bitcast double* %35 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %36
%37 = getelementptr inbounds double, double* %0, i64 36
%38 = bitcast double* %37 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %38
%39 = getelementptr inbounds double, double* %0, i64 38
%40 = bitcast double* %39 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %40
%41 = getelementptr inbounds double, double* %0, i64 40
%42 = bitcast double* %41 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %42
%43 = getelementptr inbounds double, double* %0, i64 42
%44 = bitcast double* %43 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %44
%45 = getelementptr inbounds double, double* %0, i64 44
%46 = bitcast double* %45 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %46
%47 = getelementptr inbounds double, double* %0, i64 46
%48 = bitcast double* %47 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %48
%49 = getelementptr inbounds double, double* %0, i64 48
%50 = bitcast double* %49 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %50
%51 = getelementptr inbounds double, double* %0, i64 50
%52 = bitcast double* %51 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %52
%53 = getelementptr inbounds double, double* %0, i64 52
%54 = bitcast double* %53 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %54
%55 = getelementptr inbounds double, double* %0, i64 54
%56 = bitcast double* %55 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %56
%57 = getelementptr inbounds double, double* %0, i64 56
%58 = bitcast double* %57 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %58
%59 = getelementptr inbounds double, double* %0, i64 58
%60 = bitcast double* %59 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %60
%61 = getelementptr inbounds double, double* %0, i64 60
%62 = bitcast double* %61 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %62
%63 = getelementptr inbounds double, double* %0, i64 62
%64 = bitcast double* %63 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %64
%65 = getelementptr inbounds double, double* %0, i64 64
%66 = bitcast double* %65 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %66
%67 = getelementptr inbounds double, double* %0, i64 66
%68 = bitcast double* %67 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %68
%69 = getelementptr inbounds double, double* %0, i64 68
%70 = bitcast double* %69 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %70
%71 = getelementptr inbounds double, double* %0, i64 70
%72 = bitcast double* %71 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %72
%73 = getelementptr inbounds double, double* %0, i64 72
%74 = bitcast double* %73 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %74
%75 = getelementptr inbounds double, double* %0, i64 74
%76 = bitcast double* %75 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %76
%77 = getelementptr inbounds double, double* %0, i64 76
%78 = bitcast double* %77 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %78
%79 = getelementptr inbounds double, double* %0, i64 78
%80 = bitcast double* %79 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %80
%81 = getelementptr inbounds double, double* %0, i64 80
%82 = bitcast double* %81 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %82
%83 = getelementptr inbounds double, double* %0, i64 82
%84 = bitcast double* %83 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %84
%85 = getelementptr inbounds double, double* %0, i64 84
%86 = bitcast double* %85 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %86
%87 = getelementptr inbounds double, double* %0, i64 86
%88 = bitcast double* %87 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %88
%89 = getelementptr inbounds double, double* %0, i64 88
%90 = bitcast double* %89 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %90
%91 = getelementptr inbounds double, double* %0, i64 90
%92 = bitcast double* %91 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %92
%93 = getelementptr inbounds double, double* %0, i64 92
%94 = bitcast double* %93 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %94
%95 = getelementptr inbounds double, double* %0, i64 94
%96 = bitcast double* %95 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %96
%97 = getelementptr inbounds double, double* %0, i64 96
%98 = bitcast double* %97 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %98
%99 = getelementptr inbounds double, double* %0, i64 98
%100 = bitcast double* %99 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %100
%101 = getelementptr inbounds double, double* %0, i64 100
%102 = bitcast double* %101 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %102
%103 = getelementptr inbounds double, double* %0, i64 102
%104 = bitcast double* %103 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %104
%105 = getelementptr inbounds double, double* %0, i64 104
%106 = bitcast double* %105 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %106
%107 = getelementptr inbounds double, double* %0, i64 106
%108 = bitcast double* %107 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %108
%109 = getelementptr inbounds double, double* %0, i64 108
%110 = bitcast double* %109 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %110
%111 = getelementptr inbounds double, double* %0, i64 110
%112 = bitcast double* %111 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %112
%113 = getelementptr inbounds double, double* %0, i64 112
%114 = bitcast double* %113 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %114
%115 = getelementptr inbounds double, double* %0, i64 114
%116 = bitcast double* %115 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %116
%117 = getelementptr inbounds double, double* %0, i64 116
%118 = bitcast double* %117 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %118
%119 = getelementptr inbounds double, double* %0, i64 118
%120 = bitcast double* %119 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %120
%121 = getelementptr inbounds double, double* %0, i64 120
%122 = bitcast double* %121 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %122
%123 = getelementptr inbounds double, double* %0, i64 122
%124 = bitcast double* %123 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %124
%125 = getelementptr inbounds double, double* %0, i64 124
%126 = bitcast double* %125 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %126
%127 = getelementptr inbounds double, double* %0, i64 126
%128 = bitcast double* %127 to <2 x double>*
store <2 x double> <double 1.937500e+00, double 1.937500e+00>, <2 x double>* %128
ret void
}