xref: /llvm-project/llvm/test/Transforms/InstSimplify/ConstProp/cast.ll (revision 38fffa630ee80163dc65e759392ad29798905679)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=instsimplify -S | FileCheck %s
3
4; Overflow on a float to int or int to float conversion is undefined (PR21130).
5
6define i8 @overflow_fptosi() {
7; CHECK-LABEL: @overflow_fptosi(
8; CHECK-NEXT:    ret i8 poison
9;
10  %i = fptosi double 1.56e+02 to i8
11  ret i8 %i
12}
13
14define i8 @overflow_fptoui() {
15; CHECK-LABEL: @overflow_fptoui(
16; CHECK-NEXT:    ret i8 poison
17;
18  %i = fptoui double 2.56e+02 to i8
19  ret i8 %i
20}
21
22; The maximum float is approximately 2 ** 128 which is 3.4E38.
23; The constant below is 4E38. Use a 130 bit integer to hold that
24; number; 129-bits for the value + 1 bit for the sign.
25
26define float @overflow_uitofp() {
27; CHECK-LABEL: @overflow_uitofp(
28; CHECK-NEXT:    ret float 0x7FF0000000000000
29;
30  %i = uitofp i130 400000000000000000000000000000000000000 to float
31  ret float %i
32}
33
34define float @overflow_sitofp() {
35; CHECK-LABEL: @overflow_sitofp(
36; CHECK-NEXT:    ret float 0x7FF0000000000000
37;
38  %i = sitofp i130 400000000000000000000000000000000000000 to float
39  ret float %i
40}
41
42; https://llvm.org/PR43907 - make sure that NaN doesn't morph into Inf.
43; SNaN becomes QNaN.
44
45define float @nan_f64_trunc() {
46; CHECK-LABEL: @nan_f64_trunc(
47; CHECK-NEXT:    ret float 0x7FF8000000000000
48;
49  %f = fptrunc double 0x7FF0000000000001 to float
50  ret float %f
51}
52
53; Verify again with a vector and different destination type.
54; SNaN becomes SNaN (first two elements).
55; QNaN remains QNaN (third element).
56; Lower 42 bits of NaN source payload are lost.
57
58define <3 x half> @nan_v3f64_trunc() {
59; CHECK-LABEL: @nan_v3f64_trunc(
60; CHECK-NEXT:    ret <3 x half> splat (half 0xH7E00)
61;
62  %f = fptrunc <3 x double> <double 0x7FF0020000000000, double 0x7FF003FFFFFFFFFF, double 0x7FF8000000000001> to <3 x half>
63  ret <3 x half> %f
64}
65
66define bfloat @nan_bf16_trunc() {
67; CHECK-LABEL: @nan_bf16_trunc(
68; CHECK-NEXT:    ret bfloat 0xR7FC0
69;
70  %f = fptrunc double 0x7FF0000000000001 to bfloat
71  ret bfloat %f
72}
73
74define float @trunc_denorm_lost_fraction0() {
75; CHECK-LABEL: @trunc_denorm_lost_fraction0(
76; CHECK-NEXT:    ret float 0.000000e+00
77;
78  %b = fptrunc double 0x0000000010000000 to float
79  ret float %b
80}
81
82define float @trunc_denorm_lost_fraction1() {
83; CHECK-LABEL: @trunc_denorm_lost_fraction1(
84; CHECK-NEXT:    ret float 0.000000e+00
85;
86  %b = fptrunc double 0x0000000010000001 to float
87  ret float %b
88}
89
90define float @trunc_denorm_lost_fraction2() {
91; CHECK-LABEL: @trunc_denorm_lost_fraction2(
92; CHECK-NEXT:    ret float 0.000000e+00
93;
94  %b = fptrunc double 0x000000001fffffff to float
95  ret float %b
96}
97
98define float @trunc_denorm_lost_fraction3() {
99; CHECK-LABEL: @trunc_denorm_lost_fraction3(
100; CHECK-NEXT:    ret float 0.000000e+00
101;
102  %b = fptrunc double 0x0000000020000000 to float
103  ret float %b
104}
105
106define float @trunc_denorm_lost_fraction4() {
107; CHECK-LABEL: @trunc_denorm_lost_fraction4(
108; CHECK-NEXT:    ret float -0.000000e+00
109;
110  %b = fptrunc double 0x8000000010000001 to float
111  ret float %b
112}
113