[lld] [llvm] [AArch64][ELF] Section alignment of 4 for AArch64 instruction (PR #114031)

Florin Popa via llvm-commits llvm-commits at lists.llvm.org
Wed Feb 19 23:23:51 PST 2025


https://github.com/popaflorin updated https://github.com/llvm/llvm-project/pull/114031

>From cd58fa65328b648fa8894e66f3bcb7ec5515de33 Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Tue, 29 Oct 2024 10:43:25 +0000
Subject: [PATCH 1/8] [AArch64][ELF] Section alignment of 4 for AArch64
 instruction

The integrated assembler sets a minimum alignment for the .text section of 4. However user defined sections get an alignment of 1. Unlike the GNU assembler which raises the section alignment to 4 if an AArch64 instruction is used, the integrated assembler leaves the alignment at 1
---
 llvm/lib/MC/MCParser/ELFAsmParser.cpp         |  9 ++++++++
 .../directive-arch-section-alignment.s        | 22 +++++++++++++++++++
 2 files changed, 31 insertions(+)
 create mode 100644 llvm/test/MC/AArch64/directive-arch-section-alignment.s

diff --git a/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index 99b13c68a9966..978823359b17f 100644
--- a/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
@@ -700,6 +700,15 @@ bool ELFAsmParser::parseSectionArguments(bool IsPush, SMLoc loc) {
       getContext().getELFSection(SectionName, Type, Flags, Size, GroupName,
                                  IsComdat, UniqueID, LinkedToSym);
   getStreamer().switchSection(Section, Subsection);
+
+  // Section alignment of 4 if an AArch64 instruction is used when $x mapping
+  // symbol is added Match GNU Assembler
+  const Triple &TT = getContext().getTargetTriple();
+  if ((Section->getFlags() & ELF::SHF_EXECINSTR) && (TT.isAArch64())) {
+    if (Section->getAlign() < 4)
+      getStreamer().emitValueToAlignment(Align(4));
+  }
+
   // Check that flags are used consistently. However, the GNU assembler permits
   // to leave out in subsequent uses of the same sections; for compatibility,
   // do likewise.
diff --git a/llvm/test/MC/AArch64/directive-arch-section-alignment.s b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
new file mode 100644
index 0000000000000..bf3881b9c288a
--- /dev/null
+++ b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
@@ -0,0 +1,22 @@
+// RUN: llvm-mc -triple aarch64-- -o - %s | FileCheck %s
+
+// CHECK: .section sec00
+// CHECK-NEXT: .p2align 2
+// CHECK-NEXT: nop
+.section sec00, "ax"
+nop
+nop
+// CHECK: .section sec01
+// CHECK-NEXT: .p2align 2
+// CHECK-NEXT: .p2align 2
+// CHECK-NEXT: nop
+.section sec01, "ax"
+.balign 4
+nop
+// CHECK: .section sec02
+// CHECK-NEXT: .p2align 2
+// CHECK-NEXT: .byte 1
+.section sec02, "ax"
+// CHECK-NEXT: nop
+.byte 1
+nop

>From 00922f4b7c5aa1dc3eb76393d8602069371db8ab Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Tue, 29 Oct 2024 10:43:25 +0000
Subject: [PATCH 2/8] [AArch64][ELF] Section alignment of 4 for AArch64
 instruction

The integrated assembler sets a minimum alignment for the .text section of 4. However user defined sections get an alignment of 1. Unlike the GNU assembler which raises the section alignment to 4 if an AArch64 instruction is used, the integrated assembler leaves the alignment at 1
---
 llvm/lib/MC/MCParser/ELFAsmParser.cpp         |  8 ------
 .../MCTargetDesc/AArch64ELFStreamer.cpp       |  6 +++++
 .../directive-arch-section-alignment.s        | 27 +++++++++----------
 3 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index 978823359b17f..b3653c7e5c5ed 100644
--- a/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
@@ -701,14 +701,6 @@ bool ELFAsmParser::parseSectionArguments(bool IsPush, SMLoc loc) {
                                  IsComdat, UniqueID, LinkedToSym);
   getStreamer().switchSection(Section, Subsection);
 
-  // Section alignment of 4 if an AArch64 instruction is used when $x mapping
-  // symbol is added Match GNU Assembler
-  const Triple &TT = getContext().getTargetTriple();
-  if ((Section->getFlags() & ELF::SHF_EXECINSTR) && (TT.isAArch64())) {
-    if (Section->getAlign() < 4)
-      getStreamer().emitValueToAlignment(Align(4));
-  }
-
   // Check that flags are used consistently. However, the GNU assembler permits
   // to leave out in subsequent uses of the same sections; for compatibility,
   // do likewise.
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
index d29d383bc2312..9e6114a80a21b 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
@@ -325,6 +325,12 @@ class AArch64ELFStreamer : public MCELFStreamer {
       LastEMS = EMS_None;
 
     MCELFStreamer::changeSection(Section, Subsection);
+
+    // Section alignment of 4 to match GNU Assembler
+    if (Section->getAlign() < 4) {
+      Section->setAlignment(Align(4));
+      emitValueToAlignment(Align(4), 0, 1, 0);
+    }
   }
 
   // Reset state between object emissions
diff --git a/llvm/test/MC/AArch64/directive-arch-section-alignment.s b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
index bf3881b9c288a..0c483a8817b20 100644
--- a/llvm/test/MC/AArch64/directive-arch-section-alignment.s
+++ b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
@@ -1,22 +1,21 @@
-// RUN: llvm-mc -triple aarch64-- -o - %s | FileCheck %s
+// RUN: llvm-mc -triple aarch64-windows -filetype obj -o %t.obj %s
+// RUN: llvm-objdump -d -r %t.obj | FileCheck %s
 
-// CHECK: .section sec00
-// CHECK-NEXT: .p2align 2
-// CHECK-NEXT: nop
 .section sec00, "ax"
 nop
 nop
-// CHECK: .section sec01
-// CHECK-NEXT: .p2align 2
-// CHECK-NEXT: .p2align 2
-// CHECK-NEXT: nop
+nop
 .section sec01, "ax"
 .balign 4
 nop
-// CHECK: .section sec02
-// CHECK-NEXT: .p2align 2
-// CHECK-NEXT: .byte 1
-.section sec02, "ax"
-// CHECK-NEXT: nop
-.byte 1
 nop
+nop
+
+// CHECK: 0000000000000000 <sec00>:
+// CHECK-NEXT: 0: d503201f      nop
+// CHECK-NEXT: 4: d503201f      nop
+// CHECK-NEXT: 8: d503201f      nop
+// CHECK: 0000000000000000 <sec01>:
+// CHECK-NEXT: 0: d503201f      nop
+// CHECK-NEXT: 4: d503201f      nop
+// CHECK-NEXT: 8: d503201f      nop

>From 262d8cf6cc83a4d32a2c9bda92f862846d25eeab Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Tue, 29 Oct 2024 10:43:25 +0000
Subject: [PATCH 3/8] [AArch64][ELF] Section alignment of 4 for AArch64
 instruction

The integrated assembler sets a minimum alignment for the .text section of 4. However user defined sections get an alignment of 1. Unlike the GNU assembler which raises the section alignment to 4 if an AArch64 instruction is used, the integrated assembler leaves the alignment at 1
---
 llvm/lib/MC/MCParser/ELFAsmParser.cpp         |  1 -
 .../MCTargetDesc/AArch64ELFStreamer.cpp       |  2 +-
 .../directive-arch-section-alignment.s        | 47 ++++++++++++++-----
 3 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/llvm/lib/MC/MCParser/ELFAsmParser.cpp b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
index b3653c7e5c5ed..99b13c68a9966 100644
--- a/llvm/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/ELFAsmParser.cpp
@@ -700,7 +700,6 @@ bool ELFAsmParser::parseSectionArguments(bool IsPush, SMLoc loc) {
       getContext().getELFSection(SectionName, Type, Flags, Size, GroupName,
                                  IsComdat, UniqueID, LinkedToSym);
   getStreamer().switchSection(Section, Subsection);
-
   // Check that flags are used consistently. However, the GNU assembler permits
   // to leave out in subsequent uses of the same sections; for compatibility,
   // do likewise.
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
index 9e6114a80a21b..fbeabe12997b4 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
@@ -327,7 +327,7 @@ class AArch64ELFStreamer : public MCELFStreamer {
     MCELFStreamer::changeSection(Section, Subsection);
 
     // Section alignment of 4 to match GNU Assembler
-    if (Section->getAlign() < 4) {
+    if ((Section->getAlign() < 4) && Section->isText()) {
       Section->setAlignment(Align(4));
       emitValueToAlignment(Align(4), 0, 1, 0);
     }
diff --git a/llvm/test/MC/AArch64/directive-arch-section-alignment.s b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
index 0c483a8817b20..4c83d65db8629 100644
--- a/llvm/test/MC/AArch64/directive-arch-section-alignment.s
+++ b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
@@ -1,21 +1,44 @@
-// RUN: llvm-mc -triple aarch64-windows -filetype obj -o %t.obj %s
-// RUN: llvm-objdump -d -r %t.obj | FileCheck %s
+// RUN: llvm-mc -triple=aarch64-none-linux-gnu -filetype=obj -o %t.obj %s
+// RUN: llvm-readobj -S --sd %t.obj | FileCheck %s  --check-prefix=CHECK-OBJ
+// RUN: llvm-readelf -s  %t.obj | FileCheck %s --check-prefix=CHECK-ELF
 
 .section sec00, "ax"
+.byte 1
+.section sec01, "ax"
 nop
 nop
-nop
-.section sec01, "ax"
+.section sec02, "ax"
 .balign 4
 nop
 nop
+.section sec03, "ax"
+.byte 0
+.section sec04, "aw"
 nop
+nop
+
+// CHECK-OBJ: Name: sec00
+// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
+// CHECK-OBJ-NEXT: Flags [ (0x6)
+// CHECK-OBJ: AddressAlignment: 4
+// CHECK-OBJ: Name: sec01
+// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
+// CHECK-OBJ-NEXT: Flags [ (0x6)
+// CHECK-OBJ: AddressAlignment: 4
+// CHECK-OBJ: Name: sec02
+// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
+// CHECK-OBJ-NEXT: Flags [ (0x6)
+// CHECK-OBJ: Name: sec03
+// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
+// CHECK-OBJ-NEXT: Flags [ (0x6)
+// CHECK-OBJ: AddressAlignment: 4
+// CHECK-OBJ: Name: sec04
+// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
+// CHECK-OBJ-NEXT: Flags [ (0x3)
+// CHECK-OBJ: AddressAlignment: 1
 
-// CHECK: 0000000000000000 <sec00>:
-// CHECK-NEXT: 0: d503201f      nop
-// CHECK-NEXT: 4: d503201f      nop
-// CHECK-NEXT: 8: d503201f      nop
-// CHECK: 0000000000000000 <sec01>:
-// CHECK-NEXT: 0: d503201f      nop
-// CHECK-NEXT: 4: d503201f      nop
-// CHECK-NEXT: 8: d503201f      nop
+//CHECK-ELF: sec00             PROGBITS        0000000000000000 000040 000001 00  AX  0   0  4
+//CHECK-ELF-NEXT: sec01             PROGBITS        0000000000000000 000044 000008 00  AX  0   0  4
+//CHECK-ELF-NEXT: sec02             PROGBITS        0000000000000000 00004c 000008 00  AX  0   0  4
+//CHECK-ELF-NEXT: sec03             PROGBITS        0000000000000000 000054 000001 00  AX  0   0  4
+//CHECK-ELF-NEXT: sec04             PROGBITS        0000000000000000 000055 000008 00  WA  0   0  1

>From 471a0433713b2ae78aec04d2db469f4ccb5d809c Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Tue, 29 Oct 2024 10:43:25 +0000
Subject: [PATCH 4/8] [AArch64][ELF] Section alignment of 4 for AArch64
 instruction

The integrated assembler sets a minimum alignment for the .text section of 4. However user defined sections get an alignment of 1. Unlike the GNU assembler which raises the section alignment to 4 if an AArch64 instruction is used, the integrated assembler leaves the alignment at 1
---
 llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
index fbeabe12997b4..4d889d8daefa2 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
@@ -329,7 +329,6 @@ class AArch64ELFStreamer : public MCELFStreamer {
     // Section alignment of 4 to match GNU Assembler
     if ((Section->getAlign() < 4) && Section->isText()) {
       Section->setAlignment(Align(4));
-      emitValueToAlignment(Align(4), 0, 1, 0);
     }
   }
 

>From 18fbf0a440cd4e2680522c698ddac87df26f01ac Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Tue, 29 Oct 2024 10:43:25 +0000
Subject: [PATCH 5/8] [AArch64][ELF] Section alignment of 4 for AArch64
 instruction

The integrated assembler sets a minimum alignment for the .text section of 4. However user defined sections get an alignment of 1. Unlike the GNU assembler which raises the section alignment to 4 if an AArch64 instruction is used, the integrated assembler leaves the alignment at 1
---
 .../MCTargetDesc/AArch64ELFStreamer.cpp       |  3 +-
 .../directive-arch-section-alignment.s        | 38 ++++++-------------
 2 files changed, 12 insertions(+), 29 deletions(-)

diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
index 4d889d8daefa2..e4c07fef9da0b 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
@@ -327,9 +327,8 @@ class AArch64ELFStreamer : public MCELFStreamer {
     MCELFStreamer::changeSection(Section, Subsection);
 
     // Section alignment of 4 to match GNU Assembler
-    if ((Section->getAlign() < 4) && Section->isText()) {
+    if ((Section->getAlign() < 4) && Section->isText())
       Section->setAlignment(Align(4));
-    }
   }
 
   // Reset state between object emissions
diff --git a/llvm/test/MC/AArch64/directive-arch-section-alignment.s b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
index 4c83d65db8629..8b3be4e322cc1 100644
--- a/llvm/test/MC/AArch64/directive-arch-section-alignment.s
+++ b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
@@ -1,6 +1,5 @@
 // RUN: llvm-mc -triple=aarch64-none-linux-gnu -filetype=obj -o %t.obj %s
-// RUN: llvm-readobj -S --sd %t.obj | FileCheck %s  --check-prefix=CHECK-OBJ
-// RUN: llvm-readelf -s  %t.obj | FileCheck %s --check-prefix=CHECK-ELF
+// RUN: llvm-readobj -S --sd %t.obj | FileCheck %s
 
 .section sec00, "ax"
 .byte 1
@@ -17,28 +16,13 @@ nop
 nop
 nop
 
-// CHECK-OBJ: Name: sec00
-// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
-// CHECK-OBJ-NEXT: Flags [ (0x6)
-// CHECK-OBJ: AddressAlignment: 4
-// CHECK-OBJ: Name: sec01
-// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
-// CHECK-OBJ-NEXT: Flags [ (0x6)
-// CHECK-OBJ: AddressAlignment: 4
-// CHECK-OBJ: Name: sec02
-// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
-// CHECK-OBJ-NEXT: Flags [ (0x6)
-// CHECK-OBJ: Name: sec03
-// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
-// CHECK-OBJ-NEXT: Flags [ (0x6)
-// CHECK-OBJ: AddressAlignment: 4
-// CHECK-OBJ: Name: sec04
-// CHECK-OBJ-NEXT: Type: SHT_PROGBITS (0x1)
-// CHECK-OBJ-NEXT: Flags [ (0x3)
-// CHECK-OBJ: AddressAlignment: 1
-
-//CHECK-ELF: sec00             PROGBITS        0000000000000000 000040 000001 00  AX  0   0  4
-//CHECK-ELF-NEXT: sec01             PROGBITS        0000000000000000 000044 000008 00  AX  0   0  4
-//CHECK-ELF-NEXT: sec02             PROGBITS        0000000000000000 00004c 000008 00  AX  0   0  4
-//CHECK-ELF-NEXT: sec03             PROGBITS        0000000000000000 000054 000001 00  AX  0   0  4
-//CHECK-ELF-NEXT: sec04             PROGBITS        0000000000000000 000055 000008 00  WA  0   0  1
+// CHECK: Name: sec00
+// CHECK: AddressAlignment: 4
+// CHECK: Name: sec01
+// CHECK: AddressAlignment: 4
+// CHECK: Name: sec02
+// CHECK: AddressAlignment: 4
+// CHECK: Name: sec03
+// CHECK: AddressAlignment: 4
+// CHECK: Name: sec04
+// CHECK: AddressAlignment: 1
\ No newline at end of file

>From 2aa199fb9e4e42ccea0d4a3817c3b6a85f03b5a6 Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Wed, 19 Feb 2025 11:18:25 +0000
Subject: [PATCH 6/8] [AArch64][ELF] Updated the synthax and fixed the lld test

As a result of review feedback, updated the synthax for the change and
first attempt to fix lld test that was failing due to missalignment
---
 lld/test/ELF/aarch64-relocs.s                   | 17 +++++++++--------
 .../AArch64/MCTargetDesc/AArch64ELFStreamer.cpp |  4 ++--
 .../AArch64/directive-arch-section-alignment.s  | 12 ++++++++----
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/lld/test/ELF/aarch64-relocs.s b/lld/test/ELF/aarch64-relocs.s
index 39cfcdd38661d..266380a88bddf 100644
--- a/lld/test/ELF/aarch64-relocs.s
+++ b/lld/test/ELF/aarch64-relocs.s
@@ -42,7 +42,7 @@ mystr:
 # CHECK: Disassembly of section .R_AARCH64_ADD_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK-NEXT: <.R_AARCH64_ADD_ABS_LO12_NC>:
-# CHECK-NEXT:   21013b:       9104fc00        add     x0, x0, #319
+# CHECK-NEXT:   210140: 91051000 add x0, x0, #324
 
 .section .R_AARCH64_LDST64_ABS_LO12_NC,"ax", at progbits
   ldr x28, [x27, :lo12:foo]
@@ -56,7 +56,7 @@ foo:
 # CHECK: Disassembly of section .R_AARCH64_LDST64_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK-NEXT: <.R_AARCH64_LDST64_ABS_LO12_NC>:
-# CHECK-NEXT:   210144:       f940a77c        ldr     x28, [x27, #328]
+# CHECK-NEXT:   21014c:       f940ab7c        ldr     x28, [x27, #336]
 
 .section .SUB,"ax", at progbits
   nop
@@ -86,7 +86,7 @@ foo32:
 # CHECK: Disassembly of section .R_AARCH64_LDST32_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK-NEXT: <ldst32>:
-# CHECK-NEXT:   21015c:       bd4160a4        ldr s4, [x5, #352]
+# CHECK-NEXT:   210164:       bd4168a4     	  ldr	s4, [x5, #360]
 
 .section .R_AARCH64_LDST8_ABS_LO12_NC,"ax", at progbits
 ldst8:
@@ -101,11 +101,12 @@ foo8:
 # CHECK: Disassembly of section .R_AARCH64_LDST8_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK-NEXT: <ldst8>:
-# CHECK-NEXT:   210164:       3985a1ab        ldrsb x11, [x13, #360]
+# CHECK-NEXT:   21016c:       3985c1ab     	  ldrsb	x11, [x13, #368]
 
 .section .R_AARCH64_LDST128_ABS_LO12_NC,"ax", at progbits
 ldst128:
   ldr q20, [x19, #:lo12:foo128]
+  .balign 16
 foo128:
   .asciz "foo"
   .size mystr, 3
@@ -116,7 +117,7 @@ foo128:
 # CHECK: Disassembly of section .R_AARCH64_LDST128_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK: <ldst128>:
-# CHECK:   21016c:       3dc05e74        ldr     q20, [x19, #368]
+# CHECK:   210180:       3dc06674     	 ldr	   q20, [x19, #400]
 #foo128:
 #   210170:       66 6f 6f 00     .word
 
@@ -135,9 +136,9 @@ foo16:
 # CHECK: Disassembly of section .R_AARCH64_LDST16_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK-NEXT: <ldst16>:
-# CHECK-NEXT:   210174:       7d430271        ldr     h17, [x19, #384]
-# CHECK-NEXT:   210178:       79430261        ldrh    w1, [x19, #384]
-# CHECK-NEXT:   21017c:       79430662        ldrh    w2, [x19, #386]
+# CHECK-NEXT:   210194:       7d434271     	  ldr	    h17, [x19, #416]
+# CHECK-NEXT:   210198:       79434261     	  ldrh	  w1, [x19, #416]
+# CHECK-NEXT:   21019c:       79434662     	  ldrh	  w2, [x19, #418]
 
 .section .R_AARCH64_MOVW_UABS,"ax", at progbits
 movz1:
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
index e4c07fef9da0b..af64fceaa507e 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp
@@ -327,8 +327,8 @@ class AArch64ELFStreamer : public MCELFStreamer {
     MCELFStreamer::changeSection(Section, Subsection);
 
     // Section alignment of 4 to match GNU Assembler
-    if ((Section->getAlign() < 4) && Section->isText())
-      Section->setAlignment(Align(4));
+    if (Section->isText())
+      Section->ensureMinAlignment(Align(4));
   }
 
   // Reset state between object emissions
diff --git a/llvm/test/MC/AArch64/directive-arch-section-alignment.s b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
index 8b3be4e322cc1..c8209a55acd50 100644
--- a/llvm/test/MC/AArch64/directive-arch-section-alignment.s
+++ b/llvm/test/MC/AArch64/directive-arch-section-alignment.s
@@ -1,6 +1,5 @@
 // RUN: llvm-mc -triple=aarch64-none-linux-gnu -filetype=obj -o %t.obj %s
 // RUN: llvm-readobj -S --sd %t.obj | FileCheck %s
-
 .section sec00, "ax"
 .byte 1
 .section sec01, "ax"
@@ -11,11 +10,14 @@ nop
 nop
 nop
 .section sec03, "ax"
+.balign 8
+nop
+nop
+.section sec04, "ax"
 .byte 0
-.section sec04, "aw"
+.section sec05, "aw"
 nop
 nop
-
 // CHECK: Name: sec00
 // CHECK: AddressAlignment: 4
 // CHECK: Name: sec01
@@ -23,6 +25,8 @@ nop
 // CHECK: Name: sec02
 // CHECK: AddressAlignment: 4
 // CHECK: Name: sec03
-// CHECK: AddressAlignment: 4
+// CHECK: AddressAlignment: 8
 // CHECK: Name: sec04
+// CHECK: AddressAlignment: 4
+// CHECK: Name: sec05
 // CHECK: AddressAlignment: 1
\ No newline at end of file

>From 1483be73573a8f10cf26d4e1dcfc64b2cc0aaf42 Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Wed, 19 Feb 2025 11:18:25 +0000
Subject: [PATCH 7/8] [AArch64][ELF] Updated the synthax and fixed the lld test

As a result of review feedback, updated the synthax for the change and
first attempt to fix lld test that was failing due to missalignment
---
 lld/test/ELF/aarch64-relocs.s | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lld/test/ELF/aarch64-relocs.s b/lld/test/ELF/aarch64-relocs.s
index 266380a88bddf..143b0fc56bf29 100644
--- a/lld/test/ELF/aarch64-relocs.s
+++ b/lld/test/ELF/aarch64-relocs.s
@@ -111,15 +111,16 @@ foo128:
   .asciz "foo"
   .size mystr, 3
 
-# S = 0x21016c, A = 0x4
-# R = ((S + A) & 0xFF8) << 6 = 0x00005c00
-# 0x00005c00 | 0x3dc00274 = 0x3dc05e74
+# S = 210180, A = 0x4
+# R = ((S + A) & 0xFF8) << 6 = 0x00006000
+# 0x00006000 | 0x3dc00274 = 0x3dc06274
 # CHECK: Disassembly of section .R_AARCH64_LDST128_ABS_LO12_NC:
 # CHECK-EMPTY:
 # CHECK: <ldst128>:
 # CHECK:   210180:       3dc06674     	 ldr	   q20, [x19, #400]
 #foo128:
-#   210170:       66 6f 6f 00     .word
+# CHECK: <foo128>:
+# CHECK-NEXT:  210190:       66 6f 6f 00     .word
 
 .section .R_AARCH64_LDST16_ABS_LO12_NC,"ax", at progbits
 ldst16:

>From 83c8656808c33ecfc738917da178e03946bb8118 Mon Sep 17 00:00:00 2001
From: Florin Popa <florin.popa at arm.com>
Date: Thu, 20 Feb 2025 07:22:13 +0000
Subject: [PATCH 8/8] [AArch64][ELF] Renamed and updated the target for the
 test

Renamed the test to align-code.s and changed generic aarch64 ELF
---
 .../{directive-arch-section-alignment.s => align-code.s}      | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
 rename llvm/test/MC/AArch64/{directive-arch-section-alignment.s => align-code.s} (80%)

diff --git a/llvm/test/MC/AArch64/directive-arch-section-alignment.s b/llvm/test/MC/AArch64/align-code.s
similarity index 80%
rename from llvm/test/MC/AArch64/directive-arch-section-alignment.s
rename to llvm/test/MC/AArch64/align-code.s
index c8209a55acd50..d9bbb268d2242 100644
--- a/llvm/test/MC/AArch64/directive-arch-section-alignment.s
+++ b/llvm/test/MC/AArch64/align-code.s
@@ -1,5 +1,5 @@
-// RUN: llvm-mc -triple=aarch64-none-linux-gnu -filetype=obj -o %t.obj %s
-// RUN: llvm-readobj -S --sd %t.obj | FileCheck %s
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -o %t.o %s
+// RUN: llvm-readobj -S --sd %t.o | FileCheck %s
 .section sec00, "ax"
 .byte 1
 .section sec01, "ax"



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