[llvm] [aarch64][win] Add support for import call optimization (equivalent to MSVC /d2ImportCallOptimization) (PR #121516)

[Matt Arsenault via llvm-commits]

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+// RUN: llvm-mc -triple aarch64-windows-msvc -filetype obj -o %t.obj %s
+// RUN: llvm-readobj --sections --sd --relocs %t.obj | FileCheck %s
+
+.section        nc_sect,"xr"
+normal_call:
+  str     x30, [sp, #-16]!                // 8-byte Folded Spill
+  adrp    x8, __imp_a
+  ldr     x8, [x8, :lo12:__imp_a]
+  .impcall        __imp_a
+  blr     x8
+  ldr     x30, [sp], #16                  // 8-byte Folded Reload
+  ret
+
+.section        tc_sect,"xr"
+tail_call:
+  adrp    x8, __imp_b
+  ldr     x8, [x8, :lo12:__imp_b]
+  .impcall        __imp_b
+  br     x8
+
+.section        .impcall,"yi"
+.asciz  "Imp_Call_V1"
+
+// CHECK-LABEL: Name: .impcall (2E 69 6D 70 63 61 6C 6C)
+// CHECK-NEXT:  VirtualSize: 0x0
+// CHECK-NEXT:  VirtualAddress: 0x0
+// CHECK-NEXT:  RawDataSize: 52
+// CHECK-NEXT:  PointerToRawData: 0x150
+// CHECK-NEXT:  PointerToRelocations: 0x0
+// CHECK-NEXT:  PointerToLineNumbers: 0x0
+// CHECK-NEXT:  RelocationCount: 0
+// CHECK-NEXT:  LineNumberCount: 0
+// CHECK-NEXT:  Characteristics [ (0x100200)
+// CHECK-NEXT:    IMAGE_SCN_ALIGN_1BYTES (0x100000)
+// CHECK-NEXT:    IMAGE_SCN_LNK_INFO (0x200)
+// CHECK-NEXT:  ]
+// CHECK-NEXT:  SectionData (
+// CHECK-NEXT:    0000: 496D705F 43616C6C 5F563100 14000000  |Imp_Call_V1.....|
+// CHECK-NEXT:    0010:
+// CHECK-SAME:    [[#%.2X,NCSECT:]]000000
+// CHECK-SAME:    13000000
+// CHECK-SAME:    [[#%.2X,NCOFFSET:]]000000
+// CHECK-SAME:    [[#%.2X,NCSYM:]]000000
+// CHECK-NEXT:    0020:
+// CHECK-SAME:    14000000
+// CHECK-SAME:    [[#%.2X,TCSECT:]]000000
+// CHECK-SAME:    13000000
+// CHECK-SAME:    [[#%.2X,TCOFFSET:]]000000
+// CHECK-NEXT:    0030:
+// CHECK-SAME:    [[#%.2X,TCSYM:]]000000
+// CHECK-NEXT:  )
+
+// CHECK-LABEL: Relocations [
+// CHECK-NEXT:     Section ([[#%u,NCSECT]]) nc_sect {
+// CHECK-NEXT:       0x[[#%x,NCOFFSET - 8]] IMAGE_REL_ARM64_PAGEBASE_REL21 __imp_a ([[#%u,NCSYM]])
+// CHECK-NEXT:       0x[[#%x,NCOFFSET - 4]] IMAGE_REL_ARM64_PAGEOFFSET_12L __imp_a ([[#%u,NCSYM]])
+// CHECK-NEXT:     }
+// CHECK-NEXT:     Section ([[#%u,TCSECT]]) tc_sect {
+// CHECK-NEXT:       0x[[#%x,TCOFFSET - 8]] IMAGE_REL_ARM64_PAGEBASE_REL21 __imp_b ([[#%u,TCSYM]])
+// CHECK-NEXT:       0x[[#%x,TCOFFSET - 4]] IMAGE_REL_ARM64_PAGEOFFSET_12L __imp_b ([[#%u,TCSYM]])
+// CHECK-NEXT:     }
+// CHECK-NEXT:   ]
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arsenm wrote:

End of file whitespace error 

https://github.com/llvm/llvm-project/pull/121516