1; RUN: opt --bpf-check-and-opt-ir -mtriple=bpf-pc-linux -S -o - %s | FileCheck %s 2; 3; Check unroll of getelementptr.and.load when direct memory offset is 4; used instead of field indexes. 5; 6; Source: 7; #define __ctx __attribute__((preserve_static_offset)) 8; 9; struct foo { 10; char aa; 11; char bb; 12; }; 13; 14; struct bar { 15; char a; 16; struct foo b; 17; } __ctx; 18; 19; extern void consume(char); 20; 21; void buz(struct bar *p) { 22; consume(((struct foo *)(((char*)&p->b) + 1))->bb); 23; } 24; 25; Compilation flag: 26; clang -cc1 -O2 -triple bpf -S -emit-llvm -disable-llvm-passes -o - \ 27; | opt -passes=sroa,bpf-preserve-static-offset -S -o - 28 29; Function Attrs: nounwind 30define dso_local void @buz(ptr noundef %p) #0 { 31entry: 32 %bb1 = call i8 (ptr, i1, i8, i8, i8, i1, ...) 33 @llvm.bpf.getelementptr.and.load.i8 34 (ptr readonly elementtype(i8) %p, 35 i1 false, i8 0, i8 1, i8 0, i1 true, i64 immarg 3) 36 #4, !tbaa !2 37 call void @consume(i8 noundef signext %bb1) 38 ret void 39} 40 41; CHECK: define dso_local void @buz(ptr noundef %[[p:.*]]) 42; CHECK: %[[bb11:.*]] = getelementptr inbounds i8, ptr %[[p]], i64 3 43; CHECK: %[[v2:.*]] = load i8, ptr %[[bb11]], align 1 44; CHECK: call void @consume(i8 noundef signext %[[v2]]) 45 46declare void @consume(i8 noundef signext) #1 47 48; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none) 49declare ptr @llvm.preserve.static.offset(ptr readnone) #2 50 51; Function Attrs: nocallback nofree nounwind willreturn 52declare i8 @llvm.bpf.getelementptr.and.load.i8(ptr nocapture, i1 immarg, i8 immarg, i8 immarg, i8 immarg, i1 immarg, ...) #3 53 54attributes #0 = { nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" } 55attributes #1 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" } 56attributes #2 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) } 57attributes #3 = { nocallback nofree nounwind willreturn } 58attributes #4 = { memory(argmem: read) } 59 60!llvm.module.flags = !{!0} 61!llvm.ident = !{!1} 62 63!0 = !{i32 1, !"wchar_size", i32 4} 64!1 = !{!"clang"} 65!2 = !{!3, !4, i64 1} 66!3 = !{!"foo", !4, i64 0, !4, i64 1} 67!4 = !{!"omnipotent char", !5, i64 0} 68!5 = !{!"Simple C/C++ TBAA"} 69