xref: /llvm-project/llvm/test/Transforms/InstCombine/pow-sqrt.ll (revision 38fffa630ee80163dc65e759392ad29798905679)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=instcombine -S | FileCheck %s
3
4; Check the libcall and the intrinsic for each case with differing FMF.
5
6; The transform to sqrt is not allowed if we risk setting errno due to -INF.
7
8define double @pow_libcall_half_no_FMF(double %x) {
9; CHECK-LABEL: @pow_libcall_half_no_FMF(
10; CHECK-NEXT:    [[POW:%.*]] = call double @pow(double [[X:%.*]], double 5.000000e-01)
11; CHECK-NEXT:    ret double [[POW]]
12;
13  %pow = call double @pow(double %x, double 5.0e-01)
14  ret double %pow
15}
16
17; The transform to (non-errno setting) sqrt is allowed as long as we deal with -0.0 and -INF.
18
19define double @pow_intrinsic_half_no_FMF(double %x) {
20; CHECK-LABEL: @pow_intrinsic_half_no_FMF(
21; CHECK-NEXT:    [[SQRT:%.*]] = call double @llvm.sqrt.f64(double [[X:%.*]])
22; CHECK-NEXT:    [[ABS:%.*]] = call double @llvm.fabs.f64(double [[SQRT]])
23; CHECK-NEXT:    [[ISINF:%.*]] = fcmp oeq double [[X]], 0xFFF0000000000000
24; CHECK-NEXT:    [[POW:%.*]] = select i1 [[ISINF]], double 0x7FF0000000000000, double [[ABS]]
25; CHECK-NEXT:    ret double [[POW]]
26;
27  %pow = call double @llvm.pow.f64(double %x, double 5.0e-01)
28  ret double %pow
29}
30
31; `afn` makes no difference, but FMF are propagated/retained.
32
33; (As above) the transform to sqrt may generate EDOM due to -INF. Generally, EDOM implies
34; formation of a NaN (which then propagates). `afn` may justify returning NaN (along with
35; setting EDOM); however, the conservatively correct approach is to avoid both the NaN and
36; the EDOM.
37
38define double @pow_libcall_half_approx(double %x) {
39; CHECK-LABEL: @pow_libcall_half_approx(
40; CHECK-NEXT:    [[POW:%.*]] = call afn double @pow(double [[X:%.*]], double 5.000000e-01)
41; CHECK-NEXT:    ret double [[POW]]
42;
43  %pow = call afn double @pow(double %x, double 5.0e-01)
44  ret double %pow
45}
46
47; (As above) the transform to (non-errno setting) sqrt is allowed as long as we deal with -0.0
48; and -INF.
49
50define <2 x double> @pow_intrinsic_half_approx(<2 x double> %x) {
51; CHECK-LABEL: @pow_intrinsic_half_approx(
52; CHECK-NEXT:    [[SQRT:%.*]] = call afn <2 x double> @llvm.sqrt.v2f64(<2 x double> [[X:%.*]])
53; CHECK-NEXT:    [[ABS:%.*]] = call afn <2 x double> @llvm.fabs.v2f64(<2 x double> [[SQRT]])
54; CHECK-NEXT:    [[ISINF:%.*]] = fcmp afn oeq <2 x double> [[X]], splat (double 0xFFF0000000000000)
55; CHECK-NEXT:    [[POW:%.*]] = select afn <2 x i1> [[ISINF]], <2 x double> splat (double 0x7FF0000000000000), <2 x double> [[ABS]]
56; CHECK-NEXT:    ret <2 x double> [[POW]]
57;
58  %pow = call afn <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double 5.0e-01, double 5.0e-01>)
59  ret <2 x double> %pow
60}
61
62define float @powf_intrinsic_half_fast(float %x) {
63; CHECK-LABEL: @powf_intrinsic_half_fast(
64; CHECK-NEXT:    [[SQRT:%.*]] = call fast float @llvm.sqrt.f32(float [[X:%.*]])
65; CHECK-NEXT:    ret float [[SQRT]]
66;
67  %pow = call fast float @llvm.pow.f32(float %x, float 5.0e-01)
68  ret float %pow
69}
70
71; If we can disregard INFs, no need for a select.
72
73define double @pow_libcall_half_no_FMF_base_ninf(i32 %x) {
74; CHECK-LABEL: @pow_libcall_half_no_FMF_base_ninf(
75; CHECK-NEXT:    [[CONV:%.*]] = uitofp i32 [[X:%.*]] to double
76; CHECK-NEXT:    [[SQRT:%.*]] = call double @sqrt(double [[CONV]])
77; CHECK-NEXT:    [[ABS:%.*]] = call double @llvm.fabs.f64(double [[SQRT]])
78; CHECK-NEXT:    ret double [[ABS]]
79;
80  %conv = uitofp i32 %x to double
81  %pow = call double @pow(double %conv, double 5.0e-01)
82  ret double %pow
83}
84
85define double @pow_libcall_half_ninf(double %x) {
86; CHECK-LABEL: @pow_libcall_half_ninf(
87; CHECK-NEXT:    [[SQRT:%.*]] = call ninf double @sqrt(double [[X:%.*]])
88; CHECK-NEXT:    [[ABS:%.*]] = call ninf double @llvm.fabs.f64(double [[SQRT]])
89; CHECK-NEXT:    ret double [[ABS]]
90;
91  %pow = call ninf double @pow(double %x, double 5.0e-01)
92  ret double %pow
93}
94
95define <2 x double> @pow_intrinsic_half_ninf(<2 x double> %x) {
96; CHECK-LABEL: @pow_intrinsic_half_ninf(
97; CHECK-NEXT:    [[SQRT:%.*]] = call ninf <2 x double> @llvm.sqrt.v2f64(<2 x double> [[X:%.*]])
98; CHECK-NEXT:    [[ABS:%.*]] = call ninf <2 x double> @llvm.fabs.v2f64(<2 x double> [[SQRT]])
99; CHECK-NEXT:    ret <2 x double> [[ABS]]
100;
101  %pow = call ninf <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double 5.0e-01, double 5.0e-01>)
102  ret <2 x double> %pow
103}
104
105; If we can disregard -0.0, no need for fabs, but still (because of -INF) cannot use library sqrt.
106
107define double @pow_libcall_half_nsz(double %x) {
108; CHECK-LABEL: @pow_libcall_half_nsz(
109; CHECK-NEXT:    [[POW:%.*]] = call nsz double @pow(double [[X:%.*]], double 5.000000e-01)
110; CHECK-NEXT:    ret double [[POW]]
111;
112  %pow = call nsz double @pow(double %x, double 5.0e-01)
113  ret double %pow
114}
115
116define double @pow_intrinsic_half_nsz(double %x) {
117; CHECK-LABEL: @pow_intrinsic_half_nsz(
118; CHECK-NEXT:    [[SQRT:%.*]] = call nsz double @llvm.sqrt.f64(double [[X:%.*]])
119; CHECK-NEXT:    [[ISINF:%.*]] = fcmp nsz oeq double [[X]], 0xFFF0000000000000
120; CHECK-NEXT:    [[POW:%.*]] = select nsz i1 [[ISINF]], double 0x7FF0000000000000, double [[SQRT]]
121; CHECK-NEXT:    ret double [[POW]]
122;
123  %pow = call nsz double @llvm.pow.f64(double %x, double 5.0e-01)
124  ret double %pow
125}
126
127; This is just sqrt.
128
129define float @pow_libcall_half_ninf_nsz(float %x) {
130; CHECK-LABEL: @pow_libcall_half_ninf_nsz(
131; CHECK-NEXT:    [[SQRTF:%.*]] = call ninf nsz float @sqrtf(float [[X:%.*]])
132; CHECK-NEXT:    ret float [[SQRTF]]
133;
134  %pow = call ninf nsz float @powf(float %x, float 5.0e-01)
135  ret float %pow
136}
137
138define double @pow_intrinsic_half_ninf_nsz(double %x) {
139; CHECK-LABEL: @pow_intrinsic_half_ninf_nsz(
140; CHECK-NEXT:    [[SQRT:%.*]] = call ninf nsz double @llvm.sqrt.f64(double [[X:%.*]])
141; CHECK-NEXT:    ret double [[SQRT]]
142;
143  %pow = call ninf nsz double @llvm.pow.f64(double %x, double 5.0e-01)
144  ret double %pow
145}
146
147; Overspecified FMF to test propagation to the new op(s).
148
149define float @pow_libcall_half_fast(float %x) {
150; CHECK-LABEL: @pow_libcall_half_fast(
151; CHECK-NEXT:    [[SQRTF:%.*]] = call fast float @sqrtf(float [[X:%.*]])
152; CHECK-NEXT:    ret float [[SQRTF]]
153;
154  %pow = call fast float @powf(float %x, float 5.0e-01)
155  ret float %pow
156}
157
158define double @pow_intrinsic_half_fast(double %x) {
159; CHECK-LABEL: @pow_intrinsic_half_fast(
160; CHECK-NEXT:    [[SQRT:%.*]] = call fast double @llvm.sqrt.f64(double [[X:%.*]])
161; CHECK-NEXT:    ret double [[SQRT]]
162;
163  %pow = call fast double @llvm.pow.f64(double %x, double 5.0e-01)
164  ret double %pow
165}
166
167; This should not be transformed without some kind of FMF.
168; -0.5 means take the reciprocal.
169
170define float @pow_libcall_neghalf_no_FMF(float %x) {
171; CHECK-LABEL: @pow_libcall_neghalf_no_FMF(
172; CHECK-NEXT:    [[POW:%.*]] = call float @powf(float [[X:%.*]], float -5.000000e-01)
173; CHECK-NEXT:    ret float [[POW]]
174;
175  %pow = call float @powf(float %x, float -5.0e-01)
176  ret float %pow
177}
178
179; If we can disregard INFs, a call to a library sqrt is okay.
180; Transform to sqrt+fdiv because 'reassoc' allows an extra rounding step.
181; Use 'fabs' to handle -0.0 correctly.
182
183define float @pow_libcall_neghalf_reassoc_ninf(float %x) {
184; CHECK-LABEL: @pow_libcall_neghalf_reassoc_ninf(
185; CHECK-NEXT:    [[SQRTF:%.*]] = call reassoc ninf float @sqrtf(float [[X:%.*]])
186; CHECK-NEXT:    [[ABS:%.*]] = call reassoc ninf float @llvm.fabs.f32(float [[SQRTF]])
187; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv reassoc ninf float 1.000000e+00, [[ABS]]
188; CHECK-NEXT:    ret float [[RECIPROCAL]]
189;
190  %pow = call reassoc ninf float @powf(float %x, float -5.0e-01)
191  ret float %pow
192}
193
194; If we cannot disregard INFs, a call to a library sqrt is not okay.
195
196define float @pow_libcall_neghalf_afn(float %x) {
197; CHECK-LABEL: @pow_libcall_neghalf_afn(
198; CHECK-NEXT:    [[POW:%.*]] = call afn float @powf(float [[X:%.*]], float -5.000000e-01)
199; CHECK-NEXT:    ret float [[POW]]
200;
201  %pow = call afn float @powf(float %x, float -5.0e-01)
202  ret float %pow
203}
204
205; This should not be transformed without some kind of FMF.
206
207define <2 x double> @pow_intrinsic_neghalf_no_FMF(<2 x double> %x) {
208; CHECK-LABEL: @pow_intrinsic_neghalf_no_FMF(
209; CHECK-NEXT:    [[POW:%.*]] = call <2 x double> @llvm.pow.v2f64(<2 x double> [[X:%.*]], <2 x double> splat (double -5.000000e-01))
210; CHECK-NEXT:    ret <2 x double> [[POW]]
211;
212  %pow = call <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double -5.0e-01, double -5.0e-01>)
213  ret <2 x double> %pow
214}
215
216; Transform to sqrt+fdiv because 'reassoc' allows an extra rounding step.
217; Use 'fabs' to handle -0.0 correctly.
218; Use 'select' to handle -INF correctly.
219
220define <2 x double> @pow_intrinsic_neghalf_reassoc(<2 x double> %x) {
221; CHECK-LABEL: @pow_intrinsic_neghalf_reassoc(
222; CHECK-NEXT:    [[SQRT:%.*]] = call reassoc <2 x double> @llvm.sqrt.v2f64(<2 x double> [[X:%.*]])
223; CHECK-NEXT:    [[ABS:%.*]] = call reassoc <2 x double> @llvm.fabs.v2f64(<2 x double> [[SQRT]])
224; CHECK-NEXT:    [[ISINF:%.*]] = fcmp reassoc oeq <2 x double> [[X]], splat (double 0xFFF0000000000000)
225; CHECK-NEXT:    [[TMP1:%.*]] = fdiv reassoc <2 x double> splat (double 1.000000e+00), [[ABS]]
226; CHECK-NEXT:    [[RECIPROCAL:%.*]] = select <2 x i1> [[ISINF]], <2 x double> zeroinitializer, <2 x double> [[TMP1]]
227; CHECK-NEXT:    ret <2 x double> [[RECIPROCAL]]
228;
229  %pow = call reassoc <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double -5.0e-01, double -5.0e-01>)
230  ret <2 x double> %pow
231}
232
233; Transform to sqrt+fdiv because 'afn' allows an extra rounding step.
234; Use 'fabs' to handle -0.0 correctly.
235; Use 'select' to handle -INF correctly.
236
237define <2 x double> @pow_intrinsic_neghalf_afn(<2 x double> %x) {
238; CHECK-LABEL: @pow_intrinsic_neghalf_afn(
239; CHECK-NEXT:    [[SQRT:%.*]] = call afn <2 x double> @llvm.sqrt.v2f64(<2 x double> [[X:%.*]])
240; CHECK-NEXT:    [[ABS:%.*]] = call afn <2 x double> @llvm.fabs.v2f64(<2 x double> [[SQRT]])
241; CHECK-NEXT:    [[ISINF:%.*]] = fcmp afn oeq <2 x double> [[X]], splat (double 0xFFF0000000000000)
242; CHECK-NEXT:    [[TMP1:%.*]] = fdiv afn <2 x double> splat (double 1.000000e+00), [[ABS]]
243; CHECK-NEXT:    [[RECIPROCAL:%.*]] = select <2 x i1> [[ISINF]], <2 x double> zeroinitializer, <2 x double> [[TMP1]]
244; CHECK-NEXT:    ret <2 x double> [[RECIPROCAL]]
245;
246  %pow = call afn <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double -5.0e-01, double -5.0e-01>)
247  ret <2 x double> %pow
248}
249
250; If we can disregard INFs, no need for a select.
251
252define double @pow_libcall_neghalf_ninf(double %x) {
253; CHECK-LABEL: @pow_libcall_neghalf_ninf(
254; CHECK-NEXT:    [[SQRT:%.*]] = call ninf afn double @sqrt(double [[X:%.*]])
255; CHECK-NEXT:    [[ABS:%.*]] = call ninf afn double @llvm.fabs.f64(double [[SQRT]])
256; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv ninf afn double 1.000000e+00, [[ABS]]
257; CHECK-NEXT:    ret double [[RECIPROCAL]]
258;
259  %pow = call afn ninf double @pow(double %x, double -5.0e-01)
260  ret double %pow
261}
262
263define <2 x double> @pow_intrinsic_neghalf_ninf(<2 x double> %x) {
264; CHECK-LABEL: @pow_intrinsic_neghalf_ninf(
265; CHECK-NEXT:    [[SQRT:%.*]] = call ninf afn <2 x double> @llvm.sqrt.v2f64(<2 x double> [[X:%.*]])
266; CHECK-NEXT:    [[ABS:%.*]] = call ninf afn <2 x double> @llvm.fabs.v2f64(<2 x double> [[SQRT]])
267; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv ninf afn <2 x double> splat (double 1.000000e+00), [[ABS]]
268; CHECK-NEXT:    ret <2 x double> [[RECIPROCAL]]
269;
270  %pow = call afn ninf <2 x double> @llvm.pow.v2f64(<2 x double> %x, <2 x double> <double -5.0e-01, double -5.0e-01>)
271  ret <2 x double> %pow
272}
273
274; If we can disregard -0.0, no need for fabs, but still (because of -INF) cannot use library sqrt.
275
276define double @pow_libcall_neghalf_nsz(double %x) {
277; CHECK-LABEL: @pow_libcall_neghalf_nsz(
278; CHECK-NEXT:    [[POW:%.*]] = call nsz afn double @pow(double [[X:%.*]], double -5.000000e-01)
279; CHECK-NEXT:    ret double [[POW]]
280;
281  %pow = call afn nsz double @pow(double %x, double -5.0e-01)
282  ret double %pow
283}
284
285define double @pow_intrinsic_neghalf_nsz(double %x) {
286; CHECK-LABEL: @pow_intrinsic_neghalf_nsz(
287; CHECK-NEXT:    [[SQRT:%.*]] = call nsz afn double @llvm.sqrt.f64(double [[X:%.*]])
288; CHECK-NEXT:    [[ISINF:%.*]] = fcmp nsz afn oeq double [[X]], 0xFFF0000000000000
289; CHECK-NEXT:    [[TMP1:%.*]] = fdiv nsz afn double 1.000000e+00, [[SQRT]]
290; CHECK-NEXT:    [[RECIPROCAL:%.*]] = select i1 [[ISINF]], double 0.000000e+00, double [[TMP1]]
291; CHECK-NEXT:    ret double [[RECIPROCAL]]
292;
293  %pow = call afn nsz double @llvm.pow.f64(double %x, double -5.0e-01)
294  ret double %pow
295}
296
297; This is just recip-sqrt.
298
299define double @pow_intrinsic_neghalf_ninf_nsz(double %x) {
300; CHECK-LABEL: @pow_intrinsic_neghalf_ninf_nsz(
301; CHECK-NEXT:    [[SQRT:%.*]] = call ninf nsz afn double @llvm.sqrt.f64(double [[X:%.*]])
302; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv ninf nsz afn double 1.000000e+00, [[SQRT]]
303; CHECK-NEXT:    ret double [[RECIPROCAL]]
304;
305  %pow = call afn ninf nsz double @llvm.pow.f64(double %x, double -5.0e-01)
306  ret double %pow
307}
308
309define float @pow_libcall_neghalf_ninf_nsz(float %x) {
310; CHECK-LABEL: @pow_libcall_neghalf_ninf_nsz(
311; CHECK-NEXT:    [[SQRTF:%.*]] = call ninf nsz afn float @sqrtf(float [[X:%.*]])
312; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv ninf nsz afn float 1.000000e+00, [[SQRTF]]
313; CHECK-NEXT:    ret float [[RECIPROCAL]]
314;
315  %pow = call afn ninf nsz float @powf(float %x, float -5.0e-01)
316  ret float %pow
317}
318
319; Overspecified FMF to test propagation to the new op(s).
320
321define float @pow_libcall_neghalf_fast(float %x) {
322; CHECK-LABEL: @pow_libcall_neghalf_fast(
323; CHECK-NEXT:    [[SQRTF:%.*]] = call fast float @sqrtf(float [[X:%.*]])
324; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv fast float 1.000000e+00, [[SQRTF]]
325; CHECK-NEXT:    ret float [[RECIPROCAL]]
326;
327  %pow = call fast float @powf(float %x, float -5.0e-01)
328  ret float %pow
329}
330
331define double @pow_intrinsic_neghalf_fast(double %x) {
332; CHECK-LABEL: @pow_intrinsic_neghalf_fast(
333; CHECK-NEXT:    [[SQRT:%.*]] = call fast double @llvm.sqrt.f64(double [[X:%.*]])
334; CHECK-NEXT:    [[RECIPROCAL:%.*]] = fdiv fast double 1.000000e+00, [[SQRT]]
335; CHECK-NEXT:    ret double [[RECIPROCAL]]
336;
337  %pow = call fast double @llvm.pow.f64(double %x, double -5.0e-01)
338  ret double %pow
339}
340
341declare double @llvm.pow.f64(double, double) #0
342declare float @llvm.pow.f32(float, float) #0
343declare <2 x double> @llvm.pow.v2f64(<2 x double>, <2 x double>) #0
344declare <2 x float> @llvm.pow.v2f32(<2 x float>, <2 x float>) #0
345declare <4 x float> @llvm.pow.v4f32(<4 x float>, <4 x float>) #0
346declare double @pow(double, double)
347declare float @powf(float, float)
348
349attributes #0 = { nounwind readnone speculatable }
350attributes #1 = { nounwind readnone }
351