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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=bpf-ir-peephole -mtriple=bpf-pc-linux -S %s | FileCheck %s
; Source:
; #define AA 40
; struct t {
; char a[20];
; };
; void foo(ptr);
;
; int test1() {
; const int a = 8;
; char tmp[AA + sizeof(struct t) + a];
; foo(tmp);
; return 0;
; }
;
; int test2(int b) {
; const int a = 8;
; char tmp[a + b];
; foo(tmp);
; return 0;
; }
; Compilation flag:
; clang -target bpf -O2 -S -emit-llvm t.c -Xclang -disable-llvm-passes
source_filename = "t.c"
target datalayout = "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128"
target triple = "bpf"
; Function Attrs: nounwind
define dso_local i32 @test1() {
; CHECK-LABEL: @test1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = alloca i32, align 4
; CHECK-NEXT: [[SAVED_STACK:%.*]] = alloca ptr, align 8
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr [[A]])
; CHECK-NEXT: store i32 8, ptr [[A]], align 4
; CHECK-NEXT: [[VLA:%.*]] = alloca i8, i64 68, align 1
; CHECK-NEXT: call void @foo(ptr [[VLA]])
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr [[A]])
; CHECK-NEXT: ret i32 0
;
entry:
%a = alloca i32, align 4
%saved_stack = alloca ptr, align 8
call void @llvm.lifetime.start.p0(i64 4, ptr %a)
store i32 8, ptr %a, align 4
%0 = call ptr @llvm.stacksave()
store ptr %0, ptr %saved_stack, align 8
%vla = alloca i8, i64 68, align 1
call void @foo(ptr %vla)
%1 = load ptr, ptr %saved_stack, align 8
call void @llvm.stackrestore(ptr %1)
call void @llvm.lifetime.end.p0(i64 4, ptr %a)
ret i32 0
}
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture)
declare ptr @llvm.stacksave()
declare dso_local void @foo(ptr)
declare void @llvm.stackrestore(ptr)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture)
define dso_local i32 @test2(i32 %b) {
; CHECK-LABEL: @test2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[B_ADDR:%.*]] = alloca i32, align 4
; CHECK-NEXT: [[A:%.*]] = alloca i32, align 4
; CHECK-NEXT: [[SAVED_STACK:%.*]] = alloca ptr, align 8
; CHECK-NEXT: [[__VLA_EXPR0:%.*]] = alloca i64, align 8
; CHECK-NEXT: store i32 [[B:%.*]], ptr [[B_ADDR]], align 4
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr [[A]])
; CHECK-NEXT: store i32 8, ptr [[A]], align 4
; CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[B_ADDR]], align 4
; CHECK-NEXT: [[ADD:%.*]] = add nsw i32 8, [[TMP1]]
; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[ADD]] to i64
; CHECK-NEXT: [[VLA:%.*]] = alloca i8, i64 [[TMP2]], align 1
; CHECK-NEXT: store i64 [[TMP2]], ptr [[__VLA_EXPR0]], align 8
; CHECK-NEXT: call void @foo(ptr [[VLA]])
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr [[A]])
; CHECK-NEXT: ret i32 0
;
entry:
%b.addr = alloca i32, align 4
%a = alloca i32, align 4
%saved_stack = alloca ptr, align 8
%__vla_expr0 = alloca i64, align 8
store i32 %b, ptr %b.addr, align 4
call void @llvm.lifetime.start.p0(i64 4, ptr %a)
store i32 8, ptr %a, align 4
%0 = load i32, ptr %b.addr, align 4
%add = add nsw i32 8, %0
%1 = zext i32 %add to i64
%2 = call ptr @llvm.stacksave()
store ptr %2, ptr %saved_stack, align 8
%vla = alloca i8, i64 %1, align 1
store i64 %1, ptr %__vla_expr0, align 8
call void @foo(ptr %vla)
%3 = load ptr, ptr %saved_stack, align 8
call void @llvm.stackrestore(ptr %3)
call void @llvm.lifetime.end.p0(i64 4, ptr %a)
ret i32 0
}
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