[lld] [lld][ELF] Support relax R_LARCH_{ALIGN, PCALA_{HI20,LO12}, GOT_PC_{HI20,LO12}} (PR #78692)

[Fangrui Song via llvm-commits]

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+# REQUIRES: loongarch
+
+# RUN: llvm-mc --filetype=obj --triple=loongarch32 --mattr=+relax %s -o %t.32.o
+# RUN: llvm-mc --filetype=obj --triple=loongarch64 --mattr=+relax %s -o %t.64.o
+# RUN: ld.lld --section-start=.text=0x10000 --section-start=.text2=0x20000 -e 0 %t.32.o -o %t.32
+# RUN: ld.lld --section-start=.text=0x10000 --section-start=.text2=0x20000 -e 0 %t.64.o -o %t.64
+# RUN: ld.lld --section-start=.text=0x10000 --section-start=.text2=0x20000 -e 0 %t.32.o --no-relax -o %t.32n
+# RUN: ld.lld --section-start=.text=0x10000 --section-start=.text2=0x20000 -e 0 %t.64.o --no-relax -o %t.64n
+# RUN: llvm-objdump -td --no-show-raw-insn %t.32 | FileCheck %s --check-prefixes=CHECK,RELAX
+# RUN: llvm-objdump -td --no-show-raw-insn %t.64 | FileCheck %s --check-prefixes=CHECK,RELAX
+# RUN: llvm-objdump -td --no-show-raw-insn %t.32n | FileCheck %s --check-prefixes=CHECK,NOREL
+# RUN: llvm-objdump -td --no-show-raw-insn %t.64n | FileCheck %s --check-prefixes=CHECK,NOREL
+
+## Test the R_LARCH_ALIGN without symbol index.
+# RUN: llvm-mc --filetype=obj --triple=loongarch64 --mattr=+relax %s -o %t.o64.o --defsym=old=1
+# RUN: ld.lld --section-start=.text=0x10000 --section-start=.text2=0x20000 -e 0 %t.o64.o -o %t.o64
+# RUN: ld.lld --section-start=.text=0x10000 --section-start=.text2=0x20000 -e 0 %t.o64.o --no-relax -o %t.o64n
+# RUN: llvm-objdump -td --no-show-raw-insn %t.o64 | FileCheck %s --check-prefixes=CHECK,RELAX
+# RUN: llvm-objdump -td --no-show-raw-insn %t.o64n | FileCheck %s --check-prefixes=CHECK,NOREL
+
+## -r keeps section contents unchanged.
+# RUN: ld.lld -r %t.64.o -o %t.64.r
+# RUN: llvm-objdump -dr --no-show-raw-insn %t.64.r | FileCheck %s --check-prefix=CHECKR
+
+# RELAX-DAG: {{0*}}10000 l .text  {{0*}}34 .Ltext_start
+# RELAX-DAG: {{0*}}1002c l .text  {{0*}}08 .L1
+# RELAX-DAG: {{0*}}10030 l .text  {{0*}}04 .L2
+# RELAX-DAG: {{0*}}20000 l .text2 {{0*}}14 .Ltext2_start
+# NOREL-DAG: {{0*}}10000 l .text  {{0*}}44 .Ltext_start
+# NOREL-DAG: {{0*}}10038 l .text  {{0*}}0c .L1
+# NOREL-DAG: {{0*}}10040 l .text  {{0*}}04 .L2
+# NOREL-DAG: {{0*}}20000 l .text2 {{0*}}14 .Ltext2_start
+
+# CHECK:      <.Ltext_start>:
+# CHECK-NEXT:    10000:      break 1
----------------
MaskRay wrote:

For newer tests, omit addresses then they are insignificant 

https://github.com/llvm/llvm-project/pull/78692