frame-access.ll 13.4 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418
; RUN: llc -mtriple=thumbv6m-eabi -frame-pointer=none %s -o - | FileCheck %s

; struct S { int x[128]; } s;
; int f(int *, int, int, int, struct S);
; int g(int *, int, int, int, int, int);
; int h(int *, int *, int *);
; int u(int *, int *, int *, struct S, struct S);

%struct.S = type { [128 x i32] }
%struct.__va_list = type { i8* }

@s = common dso_local global %struct.S zeroinitializer, align 4

declare void @llvm.va_start(i8*)
declare dso_local i32 @g(i32*, i32, i32, i32, i32, i32) local_unnamed_addr
declare dso_local i32 @f(i32*, i32, i32, i32, %struct.S* byval align 4) local_unnamed_addr
declare dso_local i32 @h(i32*, i32*, i32*) local_unnamed_addr
declare dso_local i32 @u(i32*, i32*, i32*, %struct.S* byval align 4, %struct.S* byval align 4) local_unnamed_addr

;
; Test access to arguments, passed on stack (including varargs)
;

; Usual case, access via SP
; int test_args_sp(int a, int b, int c, int d, int e) {
;   int v[4];
;   return g(v, a, b, c, d, e);
; }
define dso_local i32 @test_args_sp(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr {
entry:
  %v = alloca [4 x i32], align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e)
  ret i32 %call
}
; CHECK-LABEL: test_args_sp
; Load `e`
; CHECK:       ldr    r0, [sp, #32]
; CHECK-NEXT:  str    r3, [sp]
; Pass `e` on stack
; CHECK-NEXT:  str    r0, [sp, #4]
; CHECK:       bl    g

; int test_varargs_sp(int a, ...) {
;   int v[4];
;   __builtin_va_list ap;
;   __builtin_va_start(ap, a);
;   return g(v, a, 0, 0, 0, 0);
; }
define dso_local i32 @test_varargs_sp(i32 %a, ...) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 4
  %ap = alloca %struct.__va_list, align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %1 = bitcast %struct.__va_list* %ap to i8*
  call void @llvm.va_start(i8* nonnull %1)
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 0, i32 0, i32 0, i32 0)
  ret i32 %call
}
; CHECK-LABEL: test_varargs_sp
; Three incoming varargs in registers
; CHECK:       sub sp, #12
; CHECK:       sub sp, #28
; Incoming arguments area is accessed via SP
; CHECK:       add r0, sp, #36
; CHECK:       stm r0!, {r1, r2, r3}

; Re-aligned stack, access via FP
; int test_args_realign(int a, int b, int c, int d, int e) {
;   __attribute__((aligned(16))) int v[4];
;   return g(v, a, b, c, d, e);
; }
; Function Attrs: nounwind
define dso_local i32 @test_args_realign(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 16
  %0 = bitcast [4 x i32]* %v to i8*
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e)
  ret i32 %call
}
; CHECK-LABEL: test_args_realign
; Setup frame pointer
; CHECK:       add r7, sp, #8
; Align stack
; CHECK:       mov  r4, sp
; CHECK-NEXT:  lsrs r4, r4, #4
; CHECK-NEXT:  lsls r4, r4, #4
; CHECK-NEXT:  mov  sp, r4
; Load `e` via FP
; CHECK:       ldr r0, [r7, #8]
; CHECK-NEXT:  str r3, [sp]
; Pass `e` as argument
; CHECK-NEXT:  str r0, [sp, #4]
; CHECK:       bl    g

; int test_varargs_realign(int a, ...) {
;   __attribute__((aligned(16))) int v[4];
;   __builtin_va_list ap;
;   __builtin_va_start(ap, a);
;   return g(v, a, 0, 0, 0, 0);
; }
define dso_local i32 @test_varargs_realign(i32 %a, ...) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 16
  %ap = alloca %struct.__va_list, align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %1 = bitcast %struct.__va_list* %ap to i8*
  call void @llvm.va_start(i8* nonnull %1)
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %call = call i32 @g(i32* nonnull %arraydecay, i32 %a, i32 0, i32 0, i32 0, i32 0)
  ret i32 %call
}
; CHECK-LABEL: test_varargs_realign
; Three incoming register varargs
; CHECK:       sub sp, #12
; Setup frame pointer
; CHECK:       add r7, sp, #8
; Align stack
; CHECK:       mov  r4, sp
; CHECK-NEXT:  lsrs r4, r4, #4
; CHECK-NEXT:  lsls r4, r4, #4
; CHECK-NEXT:  mov  sp, r4
; Incoming register varargs stored via FP
; CHECK:      mov r0, r7
; CHECK-NEXT: adds r0, #8
; CHECK-NEXT: stm r0!, {r1, r2, r3}
; VLAs present, access via FP
; int test_args_vla(int a, int b, int c, int d, int e) {
;   int v[a];
;   return g(v, a, b, c, d, e);
; }
define dso_local i32 @test_args_vla(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr  {
entry:
  %vla = alloca i32, i32 %a, align 4
  %call = call i32 @g(i32* nonnull %vla, i32 %a, i32 %b, i32 %c, i32 %d, i32 %e)
  ret i32 %call
}
; CHECK-LABEL: test_args_vla
; Setup frame pointer
; CHECK:       add r7, sp, #12
; Allocate outgoing stack arguments space
; CHECK:       sub sp, #4
; Load `e` via FP
; CHECK:       ldr r5, [r7, #8]
; Pass `d` and `e` as arguments
; CHECK-NEXT:  str r3, [sp]
; CHECK-NEXT:  str r5, [sp, #4]
; CHECK:       bl  g

; int test_varargs_vla(int a, ...) {
;   int v[a];
;   __builtin_va_list ap;
;   __builtin_va_start(ap, a);
;   return g(v, a, 0, 0, 0, 0);
; }
define dso_local i32 @test_varargs_vla(i32 %a, ...) local_unnamed_addr  {
entry:
  %ap = alloca %struct.__va_list, align 4
  %vla = alloca i32, i32 %a, align 4
  %0 = bitcast %struct.__va_list* %ap to i8*
  call void @llvm.va_start(i8* nonnull %0)
  %call = call i32 @g(i32* nonnull %vla, i32 %a, i32 0, i32 0, i32 0, i32 0)
  ret i32 %call
}
; CHECK-LABEL: test_varargs_vla
; Three incoming register varargs
; CHECK:       sub sp, #12
; Setup frame pointer
; CHECK:       add r7, sp, #8
; Register varargs stored via FP
; CHECK-DAG:  str r3, [r7, #16]
; CHECK-DAG:  str r2, [r7, #12]
; CHECK-DAG:  str r1, [r7, #8]

; Moving SP, access via SP
; int test_args_moving_sp(int a, int b, int c, int d, int e) {
;   int v[4];
;   return f(v, a, b + c + d, e, s) + h(v, v+1, v+2);
; }
define dso_local i32 @test_args_moving_sp(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %add = add nsw i32 %c, %b
  %add1 = add nsw i32 %add, %d
  %call = call i32 @f(i32* nonnull %arraydecay, i32 %a, i32 %add1, i32 %e, %struct.S* byval nonnull align 4 @s)
  %add.ptr = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 1
  %add.ptr5 = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 2
  %call6 = call i32 @h(i32* nonnull %arraydecay, i32* nonnull %add.ptr, i32* nonnull %add.ptr5)
  %add7 = add nsw i32 %call6, %call
  ret i32 %add7
}
; CHECK-LABEL: test_args_moving_sp
; 20 bytes callee-saved area
; CHECK:       push {r4, r5, r6, r7, lr}
; 20 bytes locals
; CHECK:       sub sp, #20
; Setup base pointer
; CHECK:       mov r6, sp
; Allocate outgoing arguments space
; CHECK:       sub sp, #508
; CHECK:       sub sp, #4
; Load `e` via BP, 40 = 20 + 20
; CHECK:       ldr r3, [r6, #40]
; CHECK:       bl  f
; Stack restored before next call
; CHECK-NEXT:  add sp, #508
; CHECK-NEXT:  add sp, #4
; CHECK:       bl  h

; int test_varargs_moving_sp(int a, ...) {
;   int v[4];
;   __builtin_va_list ap;
;   __builtin_va_start(ap, a);
;   return f(v, a, 0, 0, s) + h(v, v+1, v+2);
; }
define dso_local i32 @test_varargs_moving_sp(i32 %a, ...) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 4
  %ap = alloca %struct.__va_list, align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %1 = bitcast %struct.__va_list* %ap to i8*
  call void @llvm.va_start(i8* nonnull %1)
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %call = call i32 @f(i32* nonnull %arraydecay, i32 %a, i32 0, i32 0, %struct.S* byval nonnull align 4 @s)
  %add.ptr = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 1
  %add.ptr5 = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 2
  %call6 = call i32 @h(i32* nonnull %arraydecay, i32* nonnull %add.ptr, i32* nonnull %add.ptr5)
  %add = add nsw i32 %call6, %call
  ret i32 %add
}
; CHECK-LABEL: test_varargs_moving_sp
; Three incoming register varargs
; CHECK:       sub sp, #12
; 16 bytes callee-saves
; CHECK:       push {r4, r5, r6, lr}
; 20 bytes locals
; CHECK:       sub sp, #20
; Incoming varargs stored via BP, 36 = 20 + 16
; CHECK:       mov r0, r6
; CHECK-NEXT:  adds r0, #36
; CHECK-NEXT:  stm r0!, {r1, r2, r3}

;
; Access to locals
;

; Usual case, access via SP.
; int test_local(int n) {
;   int v[4];
;   int x, y, z;
;   h(&x, &y, &z);
;   return g(v, x, y, z, 0, 0);
; }
define dso_local i32 @test_local(i32 %n) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 4
  %x = alloca i32, align 4
  %y = alloca i32, align 4
  %z = alloca i32, align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %1 = bitcast i32* %x to i8*
  %2 = bitcast i32* %y to i8*
  %3 = bitcast i32* %z to i8*
  %call = call i32 @h(i32* nonnull %x, i32* nonnull %y, i32* nonnull %z)
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %4 = load i32, i32* %x, align 4
  %5 = load i32, i32* %y, align 4
  %6 = load i32, i32* %z, align 4
  %call1 = call i32 @g(i32* nonnull %arraydecay, i32 %4, i32 %5, i32 %6, i32 0, i32 0)
  ret i32 %call1
}
; CHECK-LABEL: test_local
; Arguments to `h` relative to SP
; CHECK:       add r0, sp, #20
; CHECK-NEXT:  add r1, sp, #16
; CHECK-NEXT:  add r2, sp, #12
; CHECK-NEXT:  bl  h
; Load `x`, `y`, and `z` via SP
; CHECK:       ldr r1, [sp, #20]
; CHECK-NEXT:  ldr r2, [sp, #16]
; CHECK-NEXT:  ldr r3, [sp, #12]
; CHECK:       bl  g

; Re-aligned stack, access via SP.
; int test_local_realign(int n) {
;   __attribute__((aligned(16))) int v[4];
;   int x, y, z;
;   h(&x, &y, &z);
;   return g(v, x, y, z, 0, 0);
; }
define dso_local i32 @test_local_realign(i32 %n) local_unnamed_addr  {
entry:
  %v = alloca [4 x i32], align 16
  %x = alloca i32, align 4
  %y = alloca i32, align 4
  %z = alloca i32, align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %1 = bitcast i32* %x to i8*
  %2 = bitcast i32* %y to i8*
  %3 = bitcast i32* %z to i8*
  %call = call i32 @h(i32* nonnull %x, i32* nonnull %y, i32* nonnull %z)
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %4 = load i32, i32* %x, align 4
  %5 = load i32, i32* %y, align 4
  %6 = load i32, i32* %z, align 4
  %call1 = call i32 @g(i32* nonnull %arraydecay, i32 %4, i32 %5, i32 %6, i32 0, i32 0)
  ret i32 %call1
}
; CHECK-LABEL: test_local_realign
; Setup frame pointer
; CHECK:       add r7, sp, #8
; Re-align stack
; CHECK:       mov r4, sp
; CHECK-NEXT:  lsrs r4, r4, #4
; CHECK-NEXT:  lsls r4, r4, #4
; CHECK-NEXT:  mov  sp, r4
; Arguments to `h` computed relative to SP
; CHECK:       add r0, sp, #28
; CHECK-NEXT:  add r1, sp, #24
; CHECK-NEXT:  add r2, sp, #20
; CHECK-NEXT:  bl  h
; Load `x`, `y`, and `z` via SP for passing to `g`
; CHECK:       ldr r1, [sp, #28]
; CHECK-NEXT:  ldr r2, [sp, #24]
; CHECK-NEXT:  ldr r3, [sp, #20]
; CHECK:       bl  g

; VLAs, access via BP.
; int test_local_vla(int n) {
;   int v[n];
;   int x, y, z;
;   h(&x, &y, &z);
;   return g(v, x, y, z, 0, 0);
; }
define dso_local i32 @test_local_vla(i32 %n) local_unnamed_addr  {
entry:
  %x = alloca i32, align 4
  %y = alloca i32, align 4
  %z = alloca i32, align 4
  %vla = alloca i32, i32 %n, align 4
  %0 = bitcast i32* %x to i8*
  %1 = bitcast i32* %y to i8*
  %2 = bitcast i32* %z to i8*
  %call = call i32 @h(i32* nonnull %x, i32* nonnull %y, i32* nonnull %z)
  %3 = load i32, i32* %x, align 4
  %4 = load i32, i32* %y, align 4
  %5 = load i32, i32* %z, align 4
  %call1 = call i32 @g(i32* nonnull %vla, i32 %3, i32 %4, i32 %5, i32 0, i32 0)
  ret i32 %call1
}
; CHECK-LABEL: test_local_vla
; Setup frame pointer
; CHECK:       add  r7, sp, #12
; Setup base pointer
; CHECK:       mov  r6, sp
; CHECK:       mov  r5, r6
; Arguments to `h` compute relative to BP
; CHECK:       adds r0, r6, #7
; CHECK-NEXT:  adds r0, #1
; CHECK-NEXT:  adds r1, r6, #4
; CHECK-NEXT:  mov  r2, r6
; CHECK-NEXT:  bl   h
; Load `x`, `y`, `z` via BP (r5 should still have the value of r6 from the move
; above)
; CHECK:       ldr r3, [r5]
; CHECK-NEXT:  ldr r2, [r5, #4]
; CHECK-NEXT:  ldr r1, [r5, #8]
; CHECK:       bl  g

;  Moving SP, access via SP.
; int test_local_moving_sp(int n) {
;   int v[4];
;   int x, y, z;
;   return u(v, &x, &y, s, s) + u(v, &y, &z, s, s);
; }
define dso_local i32 @test_local_moving_sp(i32 %n) local_unnamed_addr {
entry:
  %v = alloca [4 x i32], align 4
  %x = alloca i32, align 4
  %y = alloca i32, align 4
  %z = alloca i32, align 4
  %0 = bitcast [4 x i32]* %v to i8*
  %1 = bitcast i32* %x to i8*
  %2 = bitcast i32* %y to i8*
  %3 = bitcast i32* %z to i8*
  %arraydecay = getelementptr inbounds [4 x i32], [4 x i32]* %v, i32 0, i32 0
  %call = call i32 @u(i32* nonnull %arraydecay, i32* nonnull %x, i32* nonnull %y, %struct.S* byval nonnull align 4 @s, %struct.S* byval nonnull align 4 @s)
  %call2 = call i32 @u(i32* nonnull %arraydecay, i32* nonnull %y, i32* nonnull %z, %struct.S* byval nonnull align 4 @s, %struct.S* byval nonnull align 4 @s)
  %add = add nsw i32 %call2, %call
  ret i32 %add
}
; CHECK-LABEL: test_local_moving_sp
; Locals area
; CHECK:      sub sp, #36
; Setup BP
; CHECK:      mov r6, sp
; Outoging arguments
; CHECK:      sub sp, #508
; CHECK-NEXT: sub sp, #508
; CHECK-NEXT: sub sp, #8
; Argument addresses computed relative to BP
; CHECK:      adds r0, r6, #7
; CHECK-NEXT: adds r0, #13
; CHECK:      adds r1, r6, #7
; CHECK-NEXT: adds r1, #9
; CHECK:      adds r5, r6, #7
; CHECK-NEXT: adds r5, #5
; CHECK:      bl   u
; Stack restored before next call
; CHECK:      add  sp, #508
; CHECK-NEXT: add  sp, #508
; CHECK-NEXT: add  sp, #8
; CHECK:      bl   u