[BOLT] Fix r_aarch64_prelxx test

[yavtuk]

Summary

The relocation value is calculated using the formula S + A - P,
the verification of the value is performed by inversely calculating the location address

[yavtuk]

@yota9 @rafaelauler @Amir hi folks, maybe you know how to check it easier?

[Amir]

In D124270#3467983, @yavtuk wrote:

@yota9 @rafaelauler @Amir hi folks, maybe you know how to check it easier?

No easy way unfortunately. I'll pick up this patch and build/test manually on the buildbot then post the result here.

UPD: just noticed that the test doesn't run the binary. Please move this test from bolt/test/runtime/AArch64 to bolt/test/AArch64 and it would be picked up on X86 hosts and pre-merge checks.

[yavtuk]

@Amir thanks, please wait some time, I need to add alignment for data section

[Amir]

@yavtuk:
Can you please move this test from bolt/test/runtime/AArch64 to bolt/test/AArch64? It would be tested in pre-merge checks run.

[yota9]

bolt/test/AArch64/r_aarch64_prelxx.s

12

Please add -mlittle-endian flag

[Amir]

LGTM

PASS: BOLT :: AArch64/r_aarch64_prelxx.s (20 of 169)

bolt/test/AArch64/r_aarch64_prelxx.s

+// This test checks processing of R_AARCH64_PREL64/32/16 relocations
+// S + A - P = Value
+// S = P - A + Value
+
+// mul(D1,0x100) == << 8
+// mul(D2,0x10000) == << 16
+// mul(D3,0x1000000) == << 24
+
+// REQUIRES: system-linux
+
+// RUN: %clang %cflags -nostartfiles -nostdlib %s -o %t.exe -mlittle-endian \
+// RUN:     -Wl,-q -Wl,-z,max-page-size=4
+// RUN: llvm-readelf -Wa %t.exe | FileCheck %s -check-prefix=CHECKPREL
+
+// CHECKPREL:       R_AARCH64_PREL16      {{.*}} .dummy + 0
+// CHECKPREL-NEXT:  R_AARCH64_PREL32      {{.*}} _start + 4
+// CHECKPREL-NEXT:  R_AARCH64_PREL64      {{.*}} _start + 8
+
+// RUN: llvm-bolt %t.exe -o %t.bolt
+// RUN: llvm-objdump -D %t.bolt | FileCheck %s --check-prefix=CHECKPREL32
+
+// CHECKPREL32: [[#%x,DATATABLEADDR:]] <datatable>:
+// CHECKPREL32-NEXT: 00:
+// CHECKPREL32-NEXT: 04: [[#%x,D0:]] [[#%x,D1:]] [[#%x,D2:]] [[#%x,D3:]]
+
+// 4 is offset in datatable
+// 8 is addend
+// CHECKPREL32: [[#DATATABLEADDR + 4 - 8 + D0 + mul(D1,0x100) + mul(D2,0x10000) + mul(D3,0x1000000)]] <_start>:
+
+// RUN: llvm-objdump -D %t.bolt | FileCheck %s --check-prefix=CHECKPREL64
+// CHECKPREL64: [[#%x,DATATABLEADDR:]] <datatable>:
+// CHECKPREL64-NEXT: 00:
+// CHECKPREL64-NEXT: 04:
+// CHECKPREL64-NEXT: 08: [[#%x,D0:]] [[#%x,D1:]] [[#%x,D2:]] [[#%x,D3:]]
+// CHECKPREL64-NEXT: 0c: 00 00 00 00
+
+// 8 is offset in datatable
+// 12 is addend
+// CHECKPREL64: [[#DATATABLEADDR + 8 - 12 + D0 + mul(D1,0x100) + mul(D2,0x10000) + mul(D3,0x1000000)]] <_start>:
+
+  .section .text
+  .align 4
+  .globl _start
+  .type _start, %function
+_start:
+  adr x0, datatable
+  mov x0, #0
+  ret 
+
+.section .dummy, "da"
+dummy:
+  .word 0
+
+  .data
+  .align 8
+datatable:
+  .hword dummy - datatable
+  .align 2
+  .word _start - datatable
+  .xword _start - datatable

bolt/test/runtime/AArch64/r_aarch64_prelxx.s

-// This test checks processing of R_AARCH64_PREL64/32/16 relocations
-
-// RUN: %clang %cflags -nostartfiles -nostdlib %s -o %t.exe -Wl,-q \
-// RUN:     -Wl,-z,max-page-size=4
-// RUN: llvm-readelf -Wa %t.exe | FileCheck %s -check-prefix=CHECKPREL
-
-// CHECKPREL:       R_AARCH64_PREL16      {{.*}} .dummy + 0
-// CHECKPREL-NEXT:  R_AARCH64_PREL32      {{.*}} _start + 4
-// CHECKPREL-NEXT:  R_AARCH64_PREL64      {{.*}} _start + 8
-
-// RUN: llvm-bolt %t.exe -o %t.bolt
-// RUN: llvm-readobj -S --section-data %t.bolt | FileCheck %s
-
-// CHECK: Name: .data
-// CHECK: SectionData (
-// CHECK:   0000: FCFF0000 44FF3F00 44FF3F00 00000000
-// CHECK: )
-
-  .text
-  .align 4
-  .globl _start
-  .type _start, %function
-_start:
-  adr x0, datatable
-  mov x0, #0
-  ret 
-
-.section .dummy, "da"
-dummy:
-  .word 0
-
-.section .data
-datatable:
-  .hword dummy - datatable
-  .align 2
-  .word _start - datatable
-  .xword _start - datatable