[lld] [lld] Support thumb PLTs (PR #86223)

[via llvm-commits]

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@@ -0,0 +1,139 @@
+// REQUIRES: arm
+// RUN: llvm-mc -filetype=obj -arm-add-build-attributes --arch=thumb --mcpu=cortex-m33 %p/Inputs/arm-plt-reloc.s -o %t1
+// RUN: llvm-mc -filetype=obj -arm-add-build-attributes --arch=thumb --mcpu=cortex-m33 %s -o %t2
+// RUN: ld.lld %t1 %t2 -o %t
+// RUN: llvm-objdump --no-print-imm-hex -d %t | FileCheck %s
+// RUN: ld.lld -shared %t1 %t2 -o %t.so
+// RUN: llvm-objdump --no-print-imm-hex -d %t.so | FileCheck --check-prefix=DSO %s
+// RUN: llvm-readobj -S -r %t.so | FileCheck -check-prefix=DSOREL %s
+
+// RUN: llvm-mc -filetype=obj -arm-add-build-attributes --arch=thumbeb --mcpu=cortex-m33 %p/Inputs/arm-plt-reloc.s -o %t1.be
+// RUN: llvm-mc -filetype=obj -arm-add-build-attributes --arch=thumbeb --mcpu=cortex-m33 %s -o %t2.be
+// RUN: ld.lld %t1.be %t2.be -o %t.be
+// RUN: llvm-objdump --no-print-imm-hex -d %t.be | FileCheck %s
+// RUN: ld.lld -shared %t1.be %t2.be -o %t.so.be
+// RUN: llvm-objdump --no-print-imm-hex -d %t.so.be | FileCheck --check-prefix=DSO %s
+// RUN: llvm-readobj -S -r %t.so.be | FileCheck -check-prefix=DSOREL %s
+
+// RUN: ld.lld --be8 %t1.be %t2.be -o %t.be
+// RUN: llvm-objdump --no-print-imm-hex -d %t.be | FileCheck %s
+// RUN: ld.lld --be8 -shared %t1.be %t2.be -o %t.so.be
+// RUN: llvm-objdump --no-print-imm-hex -d %t.so.be | FileCheck --check-prefix=DSO %s
+// RUN: llvm-readobj -S -r %t.so.be | FileCheck -check-prefix=DSOREL %s
+
+// Test PLT entry generation
+ .text
+ .align 2
+ .globl _start
+ .type  _start,%function
+_start:
+ bl func1
+ bl func2
+ bl func3
+ b.w func1
+ b.w func2
+ b.w func3
+ beq.w func1
+ beq.w func2
+ beq.w func3
+
+// Executable, expect no PLT
+// CHECK: Disassembly of section .text:
+// CHECK-EMPTY:
+// CHECK-NEXT: <func1>:
+// CHECK-NEXT:   200b4: 4770    bx      lr
+// CHECK: <func2>:
+// CHECK-NEXT:   200b6: 4770    bx      lr
+// CHECK: <func3>:
+// CHECK-NEXT:   200b8: 4770    bx      lr
+// CHECK-NEXT:   200ba: d4d4 
+// CHECK: <_start>:
+// CHECK-NEXT:   200bc: f7ff fffa       bl      0x200b4 <func1>
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PiJoules wrote:

Done

https://github.com/llvm/llvm-project/pull/86223