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1; RUN: opt -passes=bpf-preserve-static-offset -mtriple=bpf-pc-linux -S -o - %s | FileCheck %s2;3; Check that bpf-preserve-static-offset folds GEP chains that end by4; getelementptr.and.load.5;6; Source (modified by hand):7; #define __ctx __attribute__((preserve_static_offset))8; 9; struct bar {10; int aa;11; int bb;12; };13; 14; struct foo {15; int a;16; struct bar b;17; } __ctx;18; 19; extern void consume(int);20; 21; void bar(struct foo *p) {22; consume(p->b.bb);23; }24;25; Compilation flag:26; clang -cc1 -O2 -triple bpf -S -emit-llvm -disable-llvm-passes -o - \27; | opt -passes=function(sroa) -S -o -28;29; And modified to fold last getelementptr/load as a single30; getelementptr.and.load.31 32%struct.foo = type { i32, %struct.bar }33%struct.bar = type { i32, i32 }34 35; Function Attrs: nounwind36define dso_local void @bar(ptr noundef %p) #0 {37entry:38 %0 = call ptr @llvm.preserve.static.offset(ptr %p)39 %b = getelementptr inbounds %struct.foo, ptr %0, i32 0, i32 140 %bb1 = call i32 (ptr, i1, i8, i8, i8, i1, ...)41 @llvm.bpf.getelementptr.and.load.i3242 (ptr readonly elementtype(%struct.bar) %b,43 i1 false, i8 0, i8 1, i8 2, i1 true, i32 immarg 0, i32 immarg 1)44 #4, !tbaa !245 call void @consume(i32 noundef %bb1)46 ret void47}48 49; CHECK: define dso_local void @bar(ptr noundef %[[p:.*]])50; CHECK: %[[bb1:.*]] = call i32 (ptr, i1, i8, i8, i8, i1, ...)51; CHECK-SAME: @llvm.bpf.getelementptr.and.load.i3252; CHECK-SAME: (ptr readonly elementtype(%struct.foo) %[[p]],53; CHECK-SAME: i1 false, i8 0, i8 1, i8 2, i1 true, i32 immarg 0, i32 immarg 1, i32 immarg 1)54; CHECK-SAME: #[[v2:.*]], !tbaa55; CHECK-NEXT: call void @consume(i32 noundef %[[bb1]])56; CHECK: attributes #[[v2]] = { memory(argmem: read) }57 58declare void @consume(i32 noundef) #159 60; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)61declare ptr @llvm.preserve.static.offset(ptr readnone) #262 63; Function Attrs: nocallback nofree nounwind willreturn64declare i32 @llvm.bpf.getelementptr.and.load.i32(ptr nocapture, i1 immarg, i8 immarg, i8 immarg, i8 immarg, i1 immarg, ...) #365 66attributes #0 = { nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" }67attributes #1 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" }68attributes #2 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }69attributes #3 = { nocallback nofree nounwind willreturn }70attributes #4 = { memory(argmem: read) }71 72!llvm.module.flags = !{!0}73!llvm.ident = !{!1}74 75!0 = !{i32 1, !"wchar_size", i32 4}76!1 = !{!"clang"}77!2 = !{!3, !4, i64 8}78!3 = !{!"foo", !4, i64 0, !7, i64 4}79!4 = !{!"int", !5, i64 0}80!5 = !{!"omnipotent char", !6, i64 0}81!6 = !{!"Simple C/C++ TBAA"}82!7 = !{!"bar", !4, i64 0, !4, i64 4}83