[llvm] [BOLT][RISCV] Add RISCV tests for external branch target validation (PR #223991)

[Jessica Clarke via llvm-commits]

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@@ -0,0 +1,43 @@
+## Reject a data-island target again when ignoring the source rescans its
+## references. The data word is an instruction encoding, as in assembly that
+## emits instructions as data; its mapping symbol still identifies data.
+## Both the source and target must retain their original addresses and bytes.
+
+# RUN: llvm-mc -triple=riscv64 -filetype=obj %s -o %t.o
+# RUN: ld.lld --emit-relocs -Ttext=0x10000 %t.o -o %t.exe
+# RUN: llvm-objcopy --dump-section=.text=%t.original.text %t.exe
+# RUN: llvm-bolt %t.exe -o %t.bolt 2>&1 | FileCheck %s --check-prefix=DIAG
+# RUN: llvm-nm --defined-only %t.bolt | FileCheck %s --check-prefix=ADDR --implicit-check-not=__ENTRY_
+# RUN: llvm-objcopy --dump-section=.bolt.org.text=%t.output.text %t.bolt
+# RUN: cmp %t.original.text %t.output.text
+# RUN: llvm-bolt %t.exe -o %t.skip.bolt --skip-funcs=_start 2>&1 | FileCheck %s --check-prefix=DIAG
+# RUN: llvm-nm --defined-only %t.skip.bolt | FileCheck %s --check-prefix=ADDR --implicit-check-not=__ENTRY_
+# RUN: llvm-objcopy --dump-section=.bolt.org.text=%t.skip.text %t.skip.bolt
+# RUN: cmp %t.original.text %t.skip.text
+
+## The same invalid reference must not be diagnosed repeatedly during rescans.
+# DIAG: BOLT-WARNING: ignoring entry point at address 0x1000c in constant island of function target
+# DIAG-NOT: ignoring entry point
+# DIAG-NOT: BOLT-ERROR
+# ADDR-DAG: 0000000000010000 T _start
+# ADDR-DAG: 0000000000010008 T target
+
+  .text
+  .option norvc
+  .globl _start
+  .type _start, at function
+_start:
+  beq t0, t1, .Ldata
+  ret
+  .size _start, .-_start
+
+  .globl target
+  .type target, at function
+target:
+  nop
+.Ldata:
+  .word 0xcd027057
+  ret
+  .size target, .-target
+
+  .reloc 0, R_RISCV_NONE
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jrtc27 wrote:

Maybe this is normal for BOLT tests but... what is this for?

https://github.com/llvm/llvm-project/pull/223991