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| // RUN: %clang_cc1 -triple x86_64-unknown-unknown -fblocks %s -emit-llvm -o - | FileCheck %s -check-prefix=UNINIT
// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fblocks -ftrivial-auto-var-init=pattern %s -emit-llvm -o - | FileCheck %s -check-prefix=PATTERN
// RUN: %clang_cc1 -triple x86_64-unknown-unknown -fblocks -ftrivial-auto-var-init=zero %s -emit-llvm -o - | FileCheck %s -check-prefix=ZERO
// None of the synthesized globals should contain `undef`.
// PATTERN-NOT: undef
// ZERO-NOT: undef
template<typename T> void used(T &) noexcept;
extern "C" {
// UNINIT-LABEL: test_selfinit(
// ZERO-LABEL: test_selfinit(
// ZERO: store i32 0, i32* %self, align 4
// PATTERN-LABEL: test_selfinit(
// PATTERN: store i32 -1431655766, i32* %self, align 4
void test_selfinit() {
int self = self + 1;
used(self);
}
// UNINIT-LABEL: test_block(
// ZERO-LABEL: test_block(
// ZERO: store i32 0, i32* %block
// PATTERN-LABEL: test_block(
// PATTERN: store i32 -1431655766, i32* %block
void test_block() {
__block int block;
used(block);
}
// Using the variable being initialized is typically UB in C, but for blocks we
// can be nice: they imply extra book-keeping and we can do the auto-init before
// any of said book-keeping.
//
// UNINIT-LABEL: test_block_self_init(
// ZERO-LABEL: test_block_self_init(
// ZERO: %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i8* }>, align 8
// ZERO: %captured1 = getelementptr inbounds %struct.__block_byref_captured, %struct.__block_byref_captured* %captured, i32 0, i32 4
// ZERO-NEXT: store %struct.XYZ* null, %struct.XYZ** %captured1, align 8
// ZERO: %call = call %struct.XYZ* @create(
// PATTERN-LABEL: test_block_self_init(
// PATTERN: %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i8* }>, align 8
// PATTERN: %captured1 = getelementptr inbounds %struct.__block_byref_captured, %struct.__block_byref_captured* %captured, i32 0, i32 4
// PATTERN-NEXT: store %struct.XYZ* inttoptr (i64 -6148914691236517206 to %struct.XYZ*), %struct.XYZ** %captured1, align 8
// PATTERN: %call = call %struct.XYZ* @create(
using Block = void (^)();
typedef struct XYZ {
Block block;
} * xyz_t;
void test_block_self_init() {
extern xyz_t create(Block block);
__block xyz_t captured = create(^() {
used(captured);
});
}
// Capturing with escape after initialization is also an edge case.
//
// UNINIT-LABEL: test_block_captures_self_after_init(
// ZERO-LABEL: test_block_captures_self_after_init(
// ZERO: %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i8* }>, align 8
// ZERO: %captured1 = getelementptr inbounds %struct.__block_byref_captured.1, %struct.__block_byref_captured.1* %captured, i32 0, i32 4
// ZERO-NEXT: store %struct.XYZ* null, %struct.XYZ** %captured1, align 8
// ZERO: %call = call %struct.XYZ* @create(
// PATTERN-LABEL: test_block_captures_self_after_init(
// PATTERN: %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i8* }>, align 8
// PATTERN: %captured1 = getelementptr inbounds %struct.__block_byref_captured.1, %struct.__block_byref_captured.1* %captured, i32 0, i32 4
// PATTERN-NEXT: store %struct.XYZ* inttoptr (i64 -6148914691236517206 to %struct.XYZ*), %struct.XYZ** %captured1, align 8
// PATTERN: %call = call %struct.XYZ* @create(
void test_block_captures_self_after_init() {
extern xyz_t create(Block block);
__block xyz_t captured;
captured = create(^() {
used(captured);
});
}
// This type of code is currently not handled by zero / pattern initialization.
// The test will break when that is fixed.
// UNINIT-LABEL: test_goto_unreachable_value(
// ZERO-LABEL: test_goto_unreachable_value(
// ZERO-NOT: store {{.*}}%oops
// PATTERN-LABEL: test_goto_unreachable_value(
// PATTERN-NOT: store {{.*}}%oops
void test_goto_unreachable_value() {
goto jump;
int oops;
jump:
used(oops);
}
// This type of code is currently not handled by zero / pattern initialization.
// The test will break when that is fixed.
// UNINIT-LABEL: test_goto(
// ZERO-LABEL: test_goto(
// ZERO: if.then:
// ZERO: br label %jump
// ZERO: store i32 0, i32* %oops, align 4
// ZERO: br label %jump
// ZERO: jump:
// PATTERN-LABEL: test_goto(
// PATTERN: if.then:
// PATTERN: br label %jump
// PATTERN: store i32 -1431655766, i32* %oops, align 4
// PATTERN: br label %jump
// PATTERN: jump:
void test_goto(int i) {
if (i)
goto jump;
int oops;
jump:
used(oops);
}
// This type of code is currently not handled by zero / pattern initialization.
// The test will break when that is fixed.
// UNINIT-LABEL: test_switch(
// ZERO-LABEL: test_switch(
// ZERO: sw.bb:
// ZERO-NEXT: store i32 0, i32* %oops, align 4
// ZERO: sw.bb1:
// ZERO-NEXT: call void @{{.*}}used
// PATTERN-LABEL: test_switch(
// PATTERN: sw.bb:
// PATTERN-NEXT: store i32 -1431655766, i32* %oops, align 4
// PATTERN: sw.bb1:
// PATTERN-NEXT: call void @{{.*}}used
void test_switch(int i) {
switch (i) {
case 0:
int oops;
break;
case 1:
used(oops);
}
}
// UNINIT-LABEL: test_vla(
// ZERO-LABEL: test_vla(
// ZERO: %[[SIZE:[0-9]+]] = mul nuw i64 %{{.*}}, 4
// ZERO: call void @llvm.memset{{.*}}(i8* align 16 %{{.*}}, i8 0, i64 %[[SIZE]], i1 false)
// PATTERN-LABEL: test_vla(
// PATTERN: %vla.iszerosized = icmp eq i64 %{{.*}}, 0
// PATTERN: br i1 %vla.iszerosized, label %vla-init.cont, label %vla-setup.loop
// PATTERN: vla-setup.loop:
// PATTERN: %[[SIZE:[0-9]+]] = mul nuw i64 %{{.*}}, 4
// PATTERN: %vla.begin = bitcast i32* %vla to i8*
// PATTERN: %vla.end = getelementptr inbounds i8, i8* %vla.begin, i64 %[[SIZE]]
// PATTERN: br label %vla-init.loop
// PATTERN: vla-init.loop:
// PATTERN: %vla.cur = phi i8* [ %vla.begin, %vla-setup.loop ], [ %vla.next, %vla-init.loop ]
// PATTERN: call void @llvm.memcpy{{.*}} %vla.cur, {{.*}}@__const.test_vla.vla
// PATTERN: %vla.next = getelementptr inbounds i8, i8* %vla.cur, i64 4
// PATTERN: %vla-init.isdone = icmp eq i8* %vla.next, %vla.end
// PATTERN: br i1 %vla-init.isdone, label %vla-init.cont, label %vla-init.loop
// PATTERN: vla-init.cont:
// PATTERN: call void @{{.*}}used
void test_vla(int size) {
// Variable-length arrays can't have a zero size according to C11 6.7.6.2/5.
// Neither can they be negative-sized.
//
// We don't use the former fact because some code creates zero-sized VLAs and
// doesn't use them. clang makes these share locations with other stack
// values, which leads to initialization of the wrong values.
//
// We rely on the later fact because it generates better code.
//
// Both cases are caught by UBSan.
int vla[size];
int *ptr = vla;
used(ptr);
}
// UNINIT-LABEL: test_alloca(
// ZERO-LABEL: test_alloca(
// ZERO: %[[SIZE:[a-z0-9]+]] = sext i32 %{{.*}} to i64
// ZERO-NEXT: %[[ALLOCA:[a-z0-9]+]] = alloca i8, i64 %[[SIZE]], align [[ALIGN:[0-9]+]]
// ZERO-NEXT: call void @llvm.memset{{.*}}(i8* align [[ALIGN]] %[[ALLOCA]], i8 0, i64 %[[SIZE]], i1 false)
// PATTERN-LABEL: test_alloca(
// PATTERN: %[[SIZE:[a-z0-9]+]] = sext i32 %{{.*}} to i64
// PATTERN-NEXT: %[[ALLOCA:[a-z0-9]+]] = alloca i8, i64 %[[SIZE]], align [[ALIGN:[0-9]+]]
// PATTERN-NEXT: call void @llvm.memset{{.*}}(i8* align [[ALIGN]] %[[ALLOCA]], i8 -86, i64 %[[SIZE]], i1 false)
void test_alloca(int size) {
void *ptr = __builtin_alloca(size);
used(ptr);
}
// UNINIT-LABEL: test_alloca_with_align(
// ZERO-LABEL: test_alloca_with_align(
// ZERO: %[[SIZE:[a-z0-9]+]] = sext i32 %{{.*}} to i64
// ZERO-NEXT: %[[ALLOCA:[a-z0-9]+]] = alloca i8, i64 %[[SIZE]], align 128
// ZERO-NEXT: call void @llvm.memset{{.*}}(i8* align 128 %[[ALLOCA]], i8 0, i64 %[[SIZE]], i1 false)
// PATTERN-LABEL: test_alloca_with_align(
// PATTERN: %[[SIZE:[a-z0-9]+]] = sext i32 %{{.*}} to i64
// PATTERN-NEXT: %[[ALLOCA:[a-z0-9]+]] = alloca i8, i64 %[[SIZE]], align 128
// PATTERN-NEXT: call void @llvm.memset{{.*}}(i8* align 128 %[[ALLOCA]], i8 -86, i64 %[[SIZE]], i1 false)
void test_alloca_with_align(int size) {
void *ptr = __builtin_alloca_with_align(size, 1024);
used(ptr);
}
// UNINIT-LABEL: test_struct_vla(
// ZERO-LABEL: test_struct_vla(
// ZERO: %[[SIZE:[0-9]+]] = mul nuw i64 %{{.*}}, 16
// ZERO: call void @llvm.memset{{.*}}(i8* align 16 %{{.*}}, i8 0, i64 %[[SIZE]], i1 false)
// PATTERN-LABEL: test_struct_vla(
// PATTERN: %vla.iszerosized = icmp eq i64 %{{.*}}, 0
// PATTERN: br i1 %vla.iszerosized, label %vla-init.cont, label %vla-setup.loop
// PATTERN: vla-setup.loop:
// PATTERN: %[[SIZE:[0-9]+]] = mul nuw i64 %{{.*}}, 16
// PATTERN: %vla.begin = bitcast %struct.anon* %vla to i8*
// PATTERN: %vla.end = getelementptr inbounds i8, i8* %vla.begin, i64 %[[SIZE]]
// PATTERN: br label %vla-init.loop
// PATTERN: vla-init.loop:
// PATTERN: %vla.cur = phi i8* [ %vla.begin, %vla-setup.loop ], [ %vla.next, %vla-init.loop ]
// PATTERN: call void @llvm.memcpy{{.*}} %vla.cur, {{.*}}@__const.test_struct_vla.vla
// PATTERN: %vla.next = getelementptr inbounds i8, i8* %vla.cur, i64 16
// PATTERN: %vla-init.isdone = icmp eq i8* %vla.next, %vla.end
// PATTERN: br i1 %vla-init.isdone, label %vla-init.cont, label %vla-init.loop
// PATTERN: vla-init.cont:
// PATTERN: call void @{{.*}}used
void test_struct_vla(int size) {
// Same as above, but with a struct that doesn't just memcpy.
struct {
float f;
char c;
void *ptr;
} vla[size];
void *ptr = static_cast<void*>(vla);
used(ptr);
}
// UNINIT-LABEL: test_zsa(
// ZERO-LABEL: test_zsa(
// ZERO: %zsa = alloca [0 x i32], align 4
// ZERO-NOT: %zsa
// ZERO: call void @{{.*}}used
// PATTERN-LABEL: test_zsa(
// PATTERN: %zsa = alloca [0 x i32], align 4
// PATTERN-NOT: %zsa
// PATTERN: call void @{{.*}}used
void test_zsa(int size) {
// Technically not valid, but as long as clang accepts them we should do
// something sensible (i.e. not store to the zero-size array).
int zsa[0];
used(zsa);
}
// UNINIT-LABEL: test_huge_uninit(
// ZERO-LABEL: test_huge_uninit(
// ZERO: call void @llvm.memset{{.*}}, i8 0, i64 65536,
// PATTERN-LABEL: test_huge_uninit(
// PATTERN: call void @llvm.memset{{.*}}, i8 -86, i64 65536,
void test_huge_uninit() {
// We can't emit this as an inline constant to a store instruction because
// SDNode hits an internal size limit.
char big[65536];
used(big);
}
// UNINIT-LABEL: test_huge_small_init(
// ZERO-LABEL: test_huge_small_init(
// ZERO: call void @llvm.memset{{.*}}, i8 0, i64 65536,
// ZERO: store i8 97,
// ZERO: store i8 98,
// ZERO: store i8 99,
// ZERO: store i8 100,
// PATTERN-LABEL: test_huge_small_init(
// PATTERN: call void @llvm.memset{{.*}}, i8 0, i64 65536,
// PATTERN: store i8 97,
// PATTERN: store i8 98,
// PATTERN: store i8 99,
// PATTERN: store i8 100,
void test_huge_small_init() {
char big[65536] = { 'a', 'b', 'c', 'd' };
used(big);
}
// UNINIT-LABEL: test_huge_larger_init(
// ZERO-LABEL: test_huge_larger_init(
// ZERO: call void @llvm.memcpy{{.*}} @__const.test_huge_larger_init.big, {{.*}}, i64 65536,
// PATTERN-LABEL: test_huge_larger_init(
// PATTERN: call void @llvm.memcpy{{.*}} @__const.test_huge_larger_init.big, {{.*}}, i64 65536,
void test_huge_larger_init() {
char big[65536] = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
used(big);
}
} // extern "C"
|