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| // RUN: %clang_cc1 -triple=x86_64-unknown-linux-gnu -DSTRUCT -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-STRUCT
// RUN: %clang_cc1 -triple=x86_64-unknown-linux-gnu -USTRUCT -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-NOSTRUCT
// RUN: not %clang_cc1 -triple=x86_64-unknown-linux-gnu -DIMPOSSIBLE_ODD -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-IMPOSSIBLE_ODD
// RUN: not %clang_cc1 -triple=x86_64-unknown-linux-gnu -DIMPOSSIBLE_BIG -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-IMPOSSIBLE_BIG
// RUN: %clang_cc1 -triple=x86_64-unknown-linux-gnu -DPOSSIBLE_X -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-X
// RUN: not %clang_cc1 -triple=x86_64-unknown-linux-gnu -DIMPOSSIBLE_X -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-IMPOSSIBLE_X
// RUN: not %clang_cc1 -triple=x86_64-unknown-linux-gnu -DIMPOSSIBLE_9BYTES -emit-llvm %s -o - 2>&1 | FileCheck %s --check-prefix=CHECK-IMPOSSIBLE_9BYTES
// Make sure Clang doesn't treat |lockval| as asm input.
void _raw_spin_lock(void) {
#ifdef STRUCT
struct {
unsigned short owner, next;
} lockval;
lockval.owner = 1;
lockval.next = 2;
#else
int lockval;
lockval = 3;
#endif
asm("nop"
: "=r"(lockval));
}
// CHECK-LABEL: _raw_spin_lock
// CHECK-LABEL: entry:
// CHECK-STRUCT: %lockval = alloca %struct.anon, align 2
// CHECK-STRUCT: store i16 1
// CHECK-STRUCT: store i16 2
// CHECK-STRUCT: [[RES:%[0-9]+]] = call i32 asm "nop", "=r,~{dirflag},~{fpsr},~{flags}"()
// CHECK-STRUCT: [[CAST:%[0-9]+]] = bitcast %struct.anon* %lockval to i32*
// CHECK-STRUCT: store i32 [[RES]], i32* [[CAST]], align 2
// CHECK-NOSTRUCT: %lockval = alloca i32, align 4
// CHECK-NOSTRUCT: store i32 3
// CHECK-NOSTRUCT: [[RES:%[0-9]+]] = call i32 asm "nop", "=r,~{dirflag},~{fpsr},~{flags}"()
// CHECK-NOSTRUCT: store i32 [[RES]], i32* %lockval, align 4
// Check Clang correctly handles a structure with padding.
void unusual_struct(void) {
struct {
unsigned short first;
unsigned char second;
} str;
asm("nop"
: "=r"(str));
}
// Check Clang reports an error if attempting to return a structure for which
// no direct conversion to a register is possible.
void odd_struct(void) {
#ifdef IMPOSSIBLE_ODD
struct __attribute__((__packed__)) {
unsigned short first;
unsigned char second;
} str;
asm("nop"
: "=r"(str));
#endif
}
// CHECK-IMPOSSIBLE_ODD: impossible constraint in asm: can't store value into a register
// Check Clang reports an error if attempting to return a big structure via a register.
void big_struct(void) {
#ifdef IMPOSSIBLE_BIG
struct {
long long int v1, v2, v3, v4;
} str;
asm("nop"
: "=r"(str));
#endif
}
// CHECK-IMPOSSIBLE_BIG: impossible constraint in asm: can't store value into a register
// Clang is able to emit LLVM IR for an 16-byte structure.
void x_constraint_fit() {
#ifdef POSSIBLE_X
struct S {
unsigned x[4];
} z;
asm volatile("nop"
: "=x"(z));
#endif
}
// CHECK-LABEL: x_constraint_fit
// CHECK-X: %z = alloca %struct.S, align 4
// CHECK-X: [[RES:%[0-9]+]] = call i128 asm sideeffect "nop", "=x,~{dirflag},~{fpsr},~{flags}"()
// CHECK-X: [[CAST:%[0-9]+]] = bitcast %struct.S* %z to i128*
// CHECK-X: store i128 [[RES]], i128* [[CAST]], align 4
// CHECK-X: ret
// Clang is unable to emit LLVM IR for a 32-byte structure.
void x_constraint_nofit() {
#ifdef IMPOSSIBLE_X
struct S {
unsigned x[8];
} z;
asm volatile("nop"
: "=x"(z));
#endif
}
// CHECK-IMPOSSIBLE_X: invalid output size for constraint
// http://crbug.com/999160
// Clang used to report the following message:
// "impossible constraint in asm: can't store struct into a register"
// for the assembly directive below, although there's no struct.
void crbug_999160_regtest() {
#ifdef IMPOSSIBLE_9BYTES
char buf[9];
asm(""
: "=r"(buf));
#endif
}
// CHECK-IMPOSSIBLE_9BYTES: impossible constraint in asm: can't store value into a register
|