; RUN: llc -mtriple=thumbv7-linux-gnueabi -filetype=obj < %s ; RUN: llc -mtriple=thumbv7-linux-gnueabi < %s | FileCheck %s ; This test verifies that KCFI instrumentation doesn't cause "out of range ; pc-relative fixup value" errors when generating object files. ; ; The test creates a scenario with enough KCFI-instrumented indirect calls ; (~32 bytes each) that would push a cbz/cbnz instruction out of its ±126 byte ; range if the KCFI_CHECK pseudo-instruction size is not properly accounted for. ; ; Without the fix (KCFI_CHECK returns size 0): ; - Backend thinks KCFI checks take no space ; - Generates cbz to branch over the code ; - During assembly, cbz target is >126 bytes away ; - Assembly fails with "error: out of range pc-relative fixup value" ; ; With the fix (KCFI_CHECK returns size 32 for Thumb2): ; - Backend correctly accounts for KCFI check expansion ; - Avoids cbz or uses longer-range branch instructions ; - Assembly succeeds, object file is generated declare void @external_function(i32) ; Test WITHOUT KCFI: should generate cbz since calls are small ; CHECK-LABEL: test_without_kcfi: ; CHECK: cbz ; CHECK-NOT: bic{{.*}}#1 define i32 @test_without_kcfi(ptr %callback, i32 %x) { entry: %cmp = icmp eq i32 %x, 0 br i1 %cmp, label %if_zero, label %if_nonzero if_nonzero: ; Regular (non-KCFI) indirect calls - much smaller call void %callback() call void %callback() call void %callback() call void %callback() call void %callback() call void %callback() call void @external_function(i32 %x) %add1 = add i32 %x, 1 ret i32 %add1 if_zero: call void @external_function(i32 0) ret i32 0 } ; Test WITH KCFI: should NOT generate cbz due to large KCFI checks ; CHECK-LABEL: test_with_kcfi: ; CHECK-NOT: cbz ; CHECK: bic{{.*}}#1 define i32 @test_with_kcfi(ptr %callback, i32 %x) !kcfi_type !1 { entry: %cmp = icmp eq i32 %x, 0 br i1 %cmp, label %if_zero, label %if_nonzero if_nonzero: ; Six KCFI-instrumented indirect calls (~192 bytes total, exceeds cbz range) call void %callback() [ "kcfi"(i32 12345678) ] call void %callback() [ "kcfi"(i32 12345678) ] call void %callback() [ "kcfi"(i32 12345678) ] call void %callback() [ "kcfi"(i32 12345678) ] call void %callback() [ "kcfi"(i32 12345678) ] call void %callback() [ "kcfi"(i32 12345678) ] ; Regular call to prevent optimization call void @external_function(i32 %x) %add1 = add i32 %x, 1 ret i32 %add1 if_zero: call void @external_function(i32 0) ret i32 0 } !llvm.module.flags = !{!0} !0 = !{i32 4, !"kcfi", i32 1} !1 = !{i32 12345678}