1 ; RUN: opt < %s -analyze -branch-prob | FileCheck %s 2 ; RUN: opt < %s -analyze -lazy-branch-prob | FileCheck %s 3 ; RUN: opt < %s -passes='print<branch-prob>' -disable-output 2>&1 | FileCheck %s 4 5 declare i32 @strcmp(i8*, i8*) 6 declare i32 @strncmp(i8*, i8*, i32) 7 declare i32 @strcasecmp(i8*, i8*) 8 declare i32 @strncasecmp(i8*, i8*, i32) 9 declare i32 @memcmp(i8*, i8*) 10 declare i32 @nonstrcmp(i8*, i8*) 11 12 13 ; Check that the result of strcmp is considered more likely to be nonzero than 14 ; zero, and equally likely to be (nonzero) positive or negative. 15 16 define i32 @test_strcmp_eq(i8* %p, i8* %q) { 17 ; CHECK: Printing analysis {{.*}} for function 'test_strcmp_eq' 18 entry: 19 %val = call i32 @strcmp(i8* %p, i8* %q) 20 %cond = icmp eq i32 %val, 0 21 br i1 %cond, label %then, label %else 22 ; CHECK: edge entry -> then probability is 0x30000000 / 0x80000000 = 37.50% 23 ; CHECK: edge entry -> else probability is 0x50000000 / 0x80000000 = 62.50% 24 25 then: 26 br label %exit 27 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 28 29 else: 30 br label %exit 31 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 32 33 exit: 34 %result = phi i32 [ 0, %then ], [ 1, %else ] 35 ret i32 %result 36 } 37 38 define i32 @test_strcmp_ne(i8* %p, i8* %q) { 39 ; CHECK: Printing analysis {{.*}} for function 'test_strcmp_ne' 40 entry: 41 %val = call i32 @strcmp(i8* %p, i8* %q) 42 %cond = icmp ne i32 %val, 0 43 br i1 %cond, label %then, label %else 44 ; CHECK: edge entry -> then probability is 0x50000000 / 0x80000000 = 62.50% 45 ; CHECK: edge entry -> else probability is 0x30000000 / 0x80000000 = 37.50% 46 47 then: 48 br label %exit 49 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 50 51 else: 52 br label %exit 53 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 54 55 exit: 56 %result = phi i32 [ 0, %then ], [ 1, %else ] 57 ret i32 %result 58 } 59 60 define i32 @test_strcmp_sgt(i8* %p, i8* %q) { 61 ; CHECK: Printing analysis {{.*}} for function 'test_strcmp_sgt' 62 entry: 63 %val = call i32 @strcmp(i8* %p, i8* %q) 64 %cond = icmp sgt i32 %val, 0 65 br i1 %cond, label %then, label %else 66 ; CHECK: edge entry -> then probability is 0x40000000 / 0x80000000 = 50.00% 67 ; CHECK: edge entry -> else probability is 0x40000000 / 0x80000000 = 50.00% 68 69 then: 70 br label %exit 71 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 72 73 else: 74 br label %exit 75 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 76 77 exit: 78 %result = phi i32 [ 0, %then ], [ 1, %else ] 79 ret i32 %result 80 } 81 82 define i32 @test_strcmp_slt(i8* %p, i8* %q) { 83 ; CHECK: Printing analysis {{.*}} for function 'test_strcmp_slt' 84 entry: 85 %val = call i32 @strcmp(i8* %p, i8* %q) 86 %cond = icmp slt i32 %val, 0 87 br i1 %cond, label %then, label %else 88 ; CHECK: edge entry -> then probability is 0x40000000 / 0x80000000 = 50.00% 89 ; CHECK: edge entry -> else probability is 0x40000000 / 0x80000000 = 50.00% 90 91 then: 92 br label %exit 93 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 94 95 else: 96 br label %exit 97 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 98 99 exit: 100 %result = phi i32 [ 0, %then ], [ 1, %else ] 101 ret i32 %result 102 } 103 104 105 ; Similarly check other library functions that have the same behaviour 106 107 define i32 @test_strncmp_sgt(i8* %p, i8* %q) { 108 ; CHECK: Printing analysis {{.*}} for function 'test_strncmp_sgt' 109 entry: 110 %val = call i32 @strncmp(i8* %p, i8* %q, i32 4) 111 %cond = icmp sgt i32 %val, 0 112 br i1 %cond, label %then, label %else 113 ; CHECK: edge entry -> then probability is 0x40000000 / 0x80000000 = 50.00% 114 ; CHECK: edge entry -> else probability is 0x40000000 / 0x80000000 = 50.00% 115 116 then: 117 br label %exit 118 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 119 120 else: 121 br label %exit 122 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 123 124 exit: 125 %result = phi i32 [ 0, %then ], [ 1, %else ] 126 ret i32 %result 127 } 128 129 define i32 @test_strcasecmp_sgt(i8* %p, i8* %q) { 130 ; CHECK: Printing analysis {{.*}} for function 'test_strcasecmp_sgt' 131 entry: 132 %val = call i32 @strcasecmp(i8* %p, i8* %q) 133 %cond = icmp sgt i32 %val, 0 134 br i1 %cond, label %then, label %else 135 ; CHECK: edge entry -> then probability is 0x40000000 / 0x80000000 = 50.00% 136 ; CHECK: edge entry -> else probability is 0x40000000 / 0x80000000 = 50.00% 137 138 then: 139 br label %exit 140 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 141 142 else: 143 br label %exit 144 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 145 146 exit: 147 %result = phi i32 [ 0, %then ], [ 1, %else ] 148 ret i32 %result 149 } 150 151 define i32 @test_strncasecmp_sgt(i8* %p, i8* %q) { 152 ; CHECK: Printing analysis {{.*}} for function 'test_strncasecmp_sgt' 153 entry: 154 %val = call i32 @strncasecmp(i8* %p, i8* %q, i32 4) 155 %cond = icmp sgt i32 %val, 0 156 br i1 %cond, label %then, label %else 157 ; CHECK: edge entry -> then probability is 0x40000000 / 0x80000000 = 50.00% 158 ; CHECK: edge entry -> else probability is 0x40000000 / 0x80000000 = 50.00% 159 160 then: 161 br label %exit 162 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 163 164 else: 165 br label %exit 166 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 167 168 exit: 169 %result = phi i32 [ 0, %then ], [ 1, %else ] 170 ret i32 %result 171 } 172 173 define i32 @test_memcmp_sgt(i8* %p, i8* %q) { 174 ; CHECK: Printing analysis {{.*}} for function 'test_memcmp_sgt' 175 entry: 176 %val = call i32 @memcmp(i8* %p, i8* %q) 177 %cond = icmp sgt i32 %val, 0 178 br i1 %cond, label %then, label %else 179 ; CHECK: edge entry -> then probability is 0x40000000 / 0x80000000 = 50.00% 180 ; CHECK: edge entry -> else probability is 0x40000000 / 0x80000000 = 50.00% 181 182 then: 183 br label %exit 184 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 185 186 else: 187 br label %exit 188 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 189 190 exit: 191 %result = phi i32 [ 0, %then ], [ 1, %else ] 192 ret i32 %result 193 } 194 195 196 ; Check that for the result of a call to a non-library function the default 197 ; heuristic is applied, i.e. positive more likely than negative, nonzero more 198 ; likely than zero. 199 200 define i32 @test_nonstrcmp_eq(i8* %p, i8* %q) { 201 ; CHECK: Printing analysis {{.*}} for function 'test_nonstrcmp_eq' 202 entry: 203 %val = call i32 @nonstrcmp(i8* %p, i8* %q) 204 %cond = icmp eq i32 %val, 0 205 br i1 %cond, label %then, label %else 206 ; CHECK: edge entry -> then probability is 0x30000000 / 0x80000000 = 37.50% 207 ; CHECK: edge entry -> else probability is 0x50000000 / 0x80000000 = 62.50% 208 209 then: 210 br label %exit 211 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 212 213 else: 214 br label %exit 215 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 216 217 exit: 218 %result = phi i32 [ 0, %then ], [ 1, %else ] 219 ret i32 %result 220 } 221 222 define i32 @test_nonstrcmp_ne(i8* %p, i8* %q) { 223 ; CHECK: Printing analysis {{.*}} for function 'test_nonstrcmp_ne' 224 entry: 225 %val = call i32 @nonstrcmp(i8* %p, i8* %q) 226 %cond = icmp ne i32 %val, 0 227 br i1 %cond, label %then, label %else 228 ; CHECK: edge entry -> then probability is 0x50000000 / 0x80000000 = 62.50% 229 ; CHECK: edge entry -> else probability is 0x30000000 / 0x80000000 = 37.50% 230 231 then: 232 br label %exit 233 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 234 235 else: 236 br label %exit 237 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 238 239 exit: 240 %result = phi i32 [ 0, %then ], [ 1, %else ] 241 ret i32 %result 242 } 243 244 define i32 @test_nonstrcmp_sgt(i8* %p, i8* %q) { 245 ; CHECK: Printing analysis {{.*}} for function 'test_nonstrcmp_sgt' 246 entry: 247 %val = call i32 @nonstrcmp(i8* %p, i8* %q) 248 %cond = icmp sgt i32 %val, 0 249 br i1 %cond, label %then, label %else 250 ; CHECK: edge entry -> then probability is 0x50000000 / 0x80000000 = 62.50% 251 ; CHECK: edge entry -> else probability is 0x30000000 / 0x80000000 = 37.50% 252 253 then: 254 br label %exit 255 ; CHECK: edge then -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 256 257 else: 258 br label %exit 259 ; CHECK: edge else -> exit probability is 0x80000000 / 0x80000000 = 100.00% [HOT edge] 260 261 exit: 262 %result = phi i32 [ 0, %then ], [ 1, %else ] 263 ret i32 %result 264 } 265
