[lld] [lld] Add thunks for hexagon (PR #111217)

[Brian Cain via llvm-commits]

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@@ -0,0 +1,115 @@
+# REQUIRES: hexagon
+# RUN: rm -rf %t && split-file %s %t && cd %t
+# RUN: llvm-mc -filetype=obj -triple=hexagon-unknown-elf main.s -o main.o
+# RUN: ld.lld main.o -o test
+# RUN: llvm-objdump -d --no-show-raw-insn test | FileCheck %s
+
+## Test thunk range scenarios for Hexagon R_HEX_B22_PCREL relocations.
+## R_HEX_B22_PCREL has a range of +/- 8MB (0x800000 bytes).
+
+#--- main.s
+.globl _start
+.type _start, %function
+_start:
+  call target_within_range_max
+  call target_beyond_range
+  call target_within_range_min
+  call target_beyond_range_min
+  call target_multiple_calls
+  call target_multiple_calls
+  call target_close
+  jumpr r31
+
+target_close:
+  jumpr r31
+
+## Target at maximum positive range (8MB - 4 bytes from _start)
+## We need to account for the instructions above: 7 calls + 1 jumpr = 8 * 4 = 32 bytes
+.skip 0X7fffbc
+.globl target_within_range_max
+.type target_within_range_max, %function
+target_within_range_max:
+  jumpr r31
+
+## Target just beyond maximum positive range (needs thunk)
+.skip 8
+.globl target_beyond_range
+.type target_beyond_range, %function
+target_beyond_range:
+  call target_within_range_max
+  jumpr r31
+
+## Target for multiple calls test
+.skip 0x100000
+.globl target_multiple_calls
+.type target_multiple_calls, %function
+target_multiple_calls:
+  jumpr r31
+
+## Now place targets at maximum negative range
+## We'll put these before _start in memory layout
+.section .text_negative, "ax", %progbits
+
+## Target at maximum negative range (-8MB + 4 bytes from _start)
+.globl target_within_range_min
+.type target_within_range_min, %function
+target_within_range_min:
+  call target_close
+  jumpr r31
+
+.skip 0X7ffff4
+
+## Target beyond maximum negative range (needs thunk)
+.globl target_beyond_range_min
+.type target_beyond_range_min, %function
+target_beyond_range_min:
+  jumpr r31
+
+## Verify thunk generation for targets beyond B22_PCREL range
+# CHECK: 000200b4 <__hexagon_thunk_target_within_range_min_from_.text.thunk>:
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androm3da wrote:

I've made the change but perhaps the subsequent CHECK-NEXT lines should also be indented?  Or does it look okay as-is?

https://github.com/llvm/llvm-project/pull/111217