[llvm] [BOLT][BTI] Refactor: move applyBTIFixup under MCPlusBuilder (PR #177164)

[Gergely Bálint via llvm-commits]

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@@ -0,0 +1,30 @@
+// Make sure that during the Hugify pass BOLT adds a BTI instruction to _start.
+
+#include <stdio.h>
+
+int main(int argc, char **argv) {
+  printf("Hello world\n");
+  return 0;
+}
+
+/*
+REQUIRES: system-linux,bolt-runtime
+
+RUN: %clang %cflags -mbranch-protection=standard -no-pie %s -o %t.nopie.exe \
+RUN: -Wl,-q,-z,force-bti
+RUN: %clang %cflags -mbranch-protection=standard -fpic %s -o %t.pie.exe \
+RUN: -Wl,-q,-z,force-bti
+
+RUN: llvm-bolt %t.nopie.exe --lite=0 -o %t.nopie --hugify | FileCheck %s \
+RUN: -check-prefix=CHECK-BOLT
+RUN: llvm-bolt %t.pie.exe --lite=0 -o %t.pie --hugify | FileCheck %s \
+RUN: -check-prefix=CHECK-BOLT
+
+CHECK-BOLT: binary is using BTI
+
+RUN: llvm-objdump -D %t.nopie | FileCheck %s -check-prefix=CHECK-OBJDUMP
+RUN: llvm-objdump -D %t.pie | FileCheck %s -check-prefix=CHECK-OBJDUMP
+
+CHECK-OBJDUMP: <_start>:
----------------
bgergely0 wrote:

If the location of the .text.injected section is fixed on different platforms, then this should be ok. I think it should be fixed, as it is BOLT that inserts this.

https://github.com/llvm/llvm-project/pull/177164