Andy Kaylor 6747139bc2
[CIR] Use zero-initializer for partial array fills (#154161)
If an array initializer list leaves eight or more elements that require
zero fill, we had been generating an individual zero element for every
one of them. This change instead follows the behavior of classic
codegen, which creates a constant structure with the specified elements
followed by a zero-initializer for the trailing zeros.
2025-08-19 12:14:05 -07:00

183 lines
7.3 KiB
C++

// RUN: %clang_cc1 -std=c++20 -triple x86_64-unknown-linux-gnu -fclangir -emit-llvm %s -o %t-cir.ll
// RUN: FileCheck --input-file=%t-cir.ll %s
int a[10];
// CHECK: @a = global [10 x i32] zeroinitializer
int aa[10][5];
// CHECK: @aa = global [10 x [5 x i32]] zeroinitializer
int c[10] = {};
// CHECK: @c = global [10 x i32] zeroinitializer
int d[3] = {1, 2, 3};
// CHECK: @d = global [3 x i32] [i32 1, i32 2, i32 3]
int dd[3][2] = {{1, 2}, {3, 4}, {5, 6}};
// CHECK: @dd = global [3 x [2 x i32]] [
// CHECK: [2 x i32] [i32 1, i32 2], [2 x i32]
// CHECK: [i32 3, i32 4], [2 x i32] [i32 5, i32 6]]
int e[10] = {1, 2};
// CHECK: @e = global <{ i32, i32, [8 x i32] }> <{ i32 1, i32 2, [8 x i32] zeroinitializer }>
int f[5] = {1, 2};
// CHECK: @f = global [5 x i32] [i32 1, i32 2, i32 0, i32 0, i32 0]
extern int b[10];
// CHECK: @b = external global [10 x i32]
extern int bb[10][5];
// CHECK: @bb = external global [10 x [5 x i32]]
// This function is only here to make sure the external globals are emitted.
void reference_externs() {
b;
bb;
}
void func() {
int arr[10];
int e = arr[0];
int e2 = arr[1];
}
// CHECK: define{{.*}} void @_Z4funcv()
// CHECK-NEXT: %[[ARR_ALLOCA:.*]] = alloca [10 x i32], i64 1, align 16
// CHECK-NEXT: %[[INIT:.*]] = alloca i32, i64 1, align 4
// CHECK-NEXT: %[[INIT_2:.*]] = alloca i32, i64 1, align 4
// CHECK-NEXT: %[[ARR_PTR:.*]] = getelementptr i32, ptr %[[ARR_ALLOCA]], i32 0
// CHECK-NEXT: %[[ELE_PTR:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i64 0
// CHECK-NEXT: %[[TMP:.*]] = load i32, ptr %[[ELE_PTR]], align 16
// CHECK-NEXT: store i32 %[[TMP]], ptr %[[INIT]], align 4
// CHECK-NEXT: %[[ARR_PTR:.*]] = getelementptr i32, ptr %[[ARR_ALLOCA]], i32 0
// CHECK-NEXT: %[[ELE_PTR:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i64 1
// CHECK-NEXT: %[[TMP:.*]] = load i32, ptr %[[ELE_PTR]], align 4
// CHECK-NEXT: store i32 %[[TMP]], ptr %[[INIT_2]], align 4
void func2() {
int arr[2] = {5};
}
// CHECK: define{{.*}} void @_Z5func2v()
// CHECK: %[[ARR:.*]] = alloca [2 x i32], i64 1, align 4
// CHECK: %[[TMP:.*]] = alloca ptr, i64 1, align 8
// CHECK: %[[ARR_PTR:.*]] = getelementptr i32, ptr %[[ARR]], i32 0
// CHECK: store i32 5, ptr %[[ARR_PTR]], align 4
// CHECK: %[[ELE_1_PTR:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i64 1
// CHECK: store ptr %[[ELE_1_PTR]], ptr %[[TMP]], align 8
// CHECK: %[[END_PTR:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i64 2
// CHECK: br label %[[LOOP_BODY:.*]]
// CHECK: [[LOOP_NEXT:.*]]:
// CHECK: %[[CUR:.*]] = load ptr, ptr %[[TMP]], align 8
// CHECK: %[[CMP:.*]] = icmp ne ptr %[[CUR]], %[[END_PTR]]
// CHECK: br i1 %[[CMP]], label %[[LOOP_BODY]], label %[[LOOP_END:.*]]
// CHECK: [[LOOP_BODY]]:
// CHECK: %[[CUR:.*]] = load ptr, ptr %[[TMP]], align 8
// CHECK: store i32 0, ptr %[[CUR]], align 4
// CHECK: %[[NEXT:.*]] = getelementptr i32, ptr %[[CUR]], i64 1
// CHECK: store ptr %[[NEXT]], ptr %[[TMP]], align 8
// CHECK: br label %[[LOOP_NEXT:.*]]
// CHECK: [[LOOP_END]]:
// CHECK: ret void
void func3() {
int arr3[2] = {5, 6};
}
// CHECK: define{{.*}} void @_Z5func3v()
// CHECK: %[[ARR_ALLOCA:.*]] = alloca [2 x i32], i64 1, align 4
// CHECK: %[[ARR_PTR:.*]] = getelementptr i32, ptr %[[ARR_ALLOCA]], i32 0
// CHECK: store i32 5, ptr %[[ARR_PTR]], align 4
// CHECK: %[[ELE_1_PTR:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i64 1
// CHECK: store i32 6, ptr %[[ELE_1_PTR]], align 4
void func4() {
int arr[2][1] = {{5}, {6}};
int e = arr[1][0];
}
// CHECK: define{{.*}} void @_Z5func4v()
// CHECK: %[[ARR_ALLOCA:.*]] = alloca [2 x [1 x i32]], i64 1, align 4
// CHECK: %[[INIT:.*]] = alloca i32, i64 1, align 4
// CHECK: %[[ARR_PTR:.*]] = getelementptr [1 x i32], ptr %[[ARR_ALLOCA]], i32 0
// CHECK: %[[ARR_0_0:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i32 0
// CHECK: store i32 5, ptr %[[ARR_0_0]], align 4
// CHECK: %[[ARR_1:.*]] = getelementptr [1 x i32], ptr %[[ARR_PTR]], i64 1
// CHECK: %[[ARR_1_0:.*]] = getelementptr i32, ptr %[[ARR_1]], i32 0
// CHECK: store i32 6, ptr %[[ARR_1_0]], align 4
// CHECK: %[[ARR_PTR:.*]] = getelementptr [1 x i32], ptr %[[ARR_ALLOCA]], i32 0
// CHECK: %[[ARR_1:.*]] = getelementptr [1 x i32], ptr %[[ARR_PTR]], i64 1
// CHECK: %[[ARR_1_0:.*]] = getelementptr i32, ptr %[[ARR_1]], i32 0
// CHECK: %[[ELE_PTR:.*]] = getelementptr i32, ptr %[[ARR_1_0]], i64 0
// CHECK: %[[TMP:.*]] = load i32, ptr %[[ELE_PTR]], align 4
// CHECK: store i32 %[[TMP]], ptr %[[INIT]], align 4
void func5() {
int arr[2][1] = {{5}};
}
// CHECK: define{{.*}} void @_Z5func5v()
// CHECK: %[[ARR:.*]] = alloca [2 x [1 x i32]], i64 1, align 4
// CHECK: %[[TMP:.*]] = alloca ptr, i64 1, align 8
// CHECK: %[[ARR_PTR:.*]] = getelementptr [1 x i32], ptr %[[ARR]], i32 0
// CHECK: %[[ARR_0:.*]] = getelementptr i32, ptr %[[ARR_PTR]], i32 0
// CHECK: store i32 5, ptr %[[ARR_0]], align 4
// CHECK: %[[ARR_1:.*]] = getelementptr [1 x i32], ptr %[[ARR_PTR]], i64 1
// CHECK: store ptr %[[ARR_1]], ptr %[[TMP]], align 8
// CHECK: %[[END_PTR:.*]] = getelementptr [1 x i32], ptr %[[ARR_PTR]], i64 2
// CHECK: br label %[[LOOP_BODY:.*]]
// CHECK: [[LOOP_NEXT:.*]]:
// CHECK: %[[CUR:.*]] = load ptr, ptr %[[TMP]], align 8
// CHECK: %[[CMP:.*]] = icmp ne ptr %[[CUR]], %[[END_PTR]]
// CHECK: br i1 %[[CMP]], label %[[LOOP_BODY]], label %[[LOOP_END:.*]]
// CHECK: [[LOOP_BODY]]:
// CHECK: %[[CUR:.*]] = load ptr, ptr %[[TMP]], align 8
// CHECK: store [1 x i32] zeroinitializer, ptr %[[CUR]], align 4
// CHECK: %[[NEXT:.*]] = getelementptr [1 x i32], ptr %[[CUR]], i64 1
// CHECK: store ptr %[[NEXT]], ptr %[[TMP]], align 8
// CHECK: br label %[[LOOP_NEXT:.*]]
// CHECK: [[LOOP_END]]:
// CHECK: ret void
void func6() {
int x = 4;
int arr[2] = { x, 5 };
}
// CHECK: define{{.*}} void @_Z5func6v()
// CHECK: %[[VAR:.*]] = alloca i32, i64 1, align 4
// CHECK: %[[ARR:.*]] = alloca [2 x i32], i64 1, align 4
// CHECK: store i32 4, ptr %[[VAR]], align 4
// CHECK: %[[ELE_0:.*]] = getelementptr i32, ptr %[[ARR]], i32 0
// CHECK: %[[TMP:.*]] = load i32, ptr %[[VAR]], align 4
// CHECK: store i32 %[[TMP]], ptr %[[ELE_0]], align 4
// CHECK: %[[ELE_1:.*]] = getelementptr i32, ptr %[[ELE_0]], i64 1
// CHECK: store i32 5, ptr %[[ELE_1]], align 4
void func7() {
int* arr[1] = {};
}
// CHECK: define{{.*}} void @_Z5func7v()
// CHECK: %[[ARR:.*]] = alloca [1 x ptr], i64 1, align 8
// CHECK: %[[TMP:.*]] = alloca ptr, i64 1, align 8
// CHECK: %[[ARR_PTR:.*]] = getelementptr ptr, ptr %[[ARR]], i32 0
// CHECK: store ptr %[[ARR_PTR]], ptr %[[TMP]], align 8
// CHECK: %[[END_PTR:.*]] = getelementptr ptr, ptr %[[ARR_PTR]], i64 1
// CHECK: br label %[[LOOP_BODY:.*]]
// CHECK: [[LOOP_NEXT:.*]]:
// CHECK: %[[CUR:.*]] = load ptr, ptr %[[TMP]], align 8
// CHECK: %[[CMP:.*]] = icmp ne ptr %[[CUR]], %[[END_PTR]]
// CHECK: br i1 %[[CMP]], label %[[LOOP_BODY]], label %[[LOOP_END:.*]]
// CHECK: [[LOOP_BODY]]:
// CHECK: %[[CUR:.*]] = load ptr, ptr %[[TMP]], align 8
// CHECK: store ptr null, ptr %[[CUR]], align 8
// CHECK: %[[NEXT:.*]] = getelementptr ptr, ptr %[[CUR]], i64 1
// CHECK: store ptr %[[NEXT]], ptr %[[TMP]], align 8
// CHECK: br label %[[LOOP_NEXT:.*]]
// CHECK: [[LOOP_END]]:
// CHECK: ret void
void func8(int p[10]) {}
// CHECK: define{{.*}} void @_Z5func8Pi(ptr {{%.*}})
// CHECK-NEXT: alloca ptr, i64 1, align 8
void func9(int pp[10][5]) {}
// CHECK: define{{.*}} void @_Z5func9PA5_i(ptr {{%.*}})
// CHECK-NEXT: alloca ptr, i64 1, align 8