[clang] [Clang][ARM]Ensure both -mno-unaligned-access and -munaligned-access are passed to multilib selection logic (PR #134099)
Simi Pallipurath via cfe-commits
cfe-commits at lists.llvm.org
Thu Apr 3 00:54:50 PDT 2025
https://github.com/simpal01 updated https://github.com/llvm/llvm-project/pull/134099
>From 7f6302053575732f633c69bbf55f2624da1e8bf4 Mon Sep 17 00:00:00 2001
From: Simi Pallipurath <simi.pallipurath at arm.com>
Date: Wed, 2 Apr 2025 12:35:16 +0100
Subject: [PATCH 1/3] Refine multilib selection to handle alignment based on
architecture features.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Update the multilib selection logic to bypass the
alignment option based on each architecture’s
feature set, rather than relying solely on command-line
options.
Previously, alignment option was bypassed only when
-mno-unaligned-access was explicitly specified on the
commandline. This change makes the selection more robust
and architecture aware.
---
clang/lib/Driver/ToolChain.cpp | 24 +++++++++----------
.../test/Driver/print-multi-selection-flags.c | 6 +++++
2 files changed, 18 insertions(+), 12 deletions(-)
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 8a922b283daf5..476026f82b32b 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -239,12 +239,12 @@ static void getAArch64MultilibFlags(const Driver &D,
Result.push_back(BranchProtectionArg->getAsString(Args));
}
- if (Arg *AlignArg = Args.getLastArg(
- options::OPT_mstrict_align, options::OPT_mno_strict_align,
- options::OPT_mno_unaligned_access, options::OPT_munaligned_access)) {
- if (AlignArg->getOption().matches(options::OPT_mstrict_align) ||
- AlignArg->getOption().matches(options::OPT_mno_unaligned_access))
- Result.push_back(AlignArg->getAsString(Args));
+ if (FeatureSet.contains("+strict-align")) {
+ Result.push_back("-mno-unaligned-access");
+ Result.push_back("-mstrict-align");
+ } else {
+ Result.push_back("-munaligned-access");
+ Result.push_back("-mno-strict-align");
}
if (Arg *Endian = Args.getLastArg(options::OPT_mbig_endian,
@@ -313,12 +313,12 @@ static void getARMMultilibFlags(const Driver &D,
Result.push_back(BranchProtectionArg->getAsString(Args));
}
- if (Arg *AlignArg = Args.getLastArg(
- options::OPT_mstrict_align, options::OPT_mno_strict_align,
- options::OPT_mno_unaligned_access, options::OPT_munaligned_access)) {
- if (AlignArg->getOption().matches(options::OPT_mstrict_align) ||
- AlignArg->getOption().matches(options::OPT_mno_unaligned_access))
- Result.push_back(AlignArg->getAsString(Args));
+ if (FeatureSet.contains("+strict-align")) {
+ Result.push_back("-mno-unaligned-access");
+ Result.push_back("-mstrict-align");
+ } else {
+ Result.push_back("-munaligned-access");
+ Result.push_back("-mno-strict-align");
}
if (Arg *Endian = Args.getLastArg(options::OPT_mbig_endian,
diff --git a/clang/test/Driver/print-multi-selection-flags.c b/clang/test/Driver/print-multi-selection-flags.c
index 5a35ae374f011..b21c2d11c1009 100644
--- a/clang/test/Driver/print-multi-selection-flags.c
+++ b/clang/test/Driver/print-multi-selection-flags.c
@@ -69,9 +69,15 @@
// CHECK-BRANCH-PROTECTION: -mbranch-protection=standard
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mno-unaligned-access | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mno-unaligned-access | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// CHECK-NO-UNALIGNED-ACCESS: -mno-unaligned-access
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -munaligned-access | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -munaligned-access | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
+// CHECK-UNALIGNED-ACCESS: -munaligned-access
+
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mbig-endian | FileCheck --check-prefix=CHECK-BIG-ENDIAN %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mbig-endian | FileCheck --check-prefix=CHECK-BIG-ENDIAN %s
// CHECK-BIG-ENDIAN: -mbig-endian
>From 0242cea7fc54c90c5fbb8a16628a14167d4377cc Mon Sep 17 00:00:00 2001
From: Simi Pallipurath <simi.pallipurath at arm.com>
Date: Wed, 2 Apr 2025 17:25:06 +0100
Subject: [PATCH 2/3] fixup! Test that test -mstrict-align/-mno-strict-align
too passed to multilib system.
---
clang/test/Driver/print-multi-selection-flags.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/clang/test/Driver/print-multi-selection-flags.c b/clang/test/Driver/print-multi-selection-flags.c
index b21c2d11c1009..ad44a5c3789ae 100644
--- a/clang/test/Driver/print-multi-selection-flags.c
+++ b/clang/test/Driver/print-multi-selection-flags.c
@@ -69,13 +69,19 @@
// CHECK-BRANCH-PROTECTION: -mbranch-protection=standard
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mno-unaligned-access | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mstrict-align | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mno-unaligned-access | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mstrict-align | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// CHECK-NO-UNALIGNED-ACCESS: -mno-unaligned-access
+// CHECK-NO-UNALIGNED-ACCESS: -mstrict-align
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mno-strict-align | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -munaligned-access | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
+// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mno-strict-align | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -munaligned-access | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
+// CHECK-UNALIGNED-ACCESS: -mno-strict-align
// CHECK-UNALIGNED-ACCESS: -munaligned-access
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mbig-endian | FileCheck --check-prefix=CHECK-BIG-ENDIAN %s
>From 6fd16087853c9ffab2ead2143eda93286e23e82f Mon Sep 17 00:00:00 2001
From: Simi Pallipurath <simi.pallipurath at arm.com>
Date: Thu, 3 Apr 2025 08:50:15 +0100
Subject: [PATCH 3/3] fixup! Address review comments by canonicalizing to
-mno-unaligned-access
---
clang/lib/Driver/ToolChain.cpp | 4 ----
clang/test/Driver/print-multi-selection-flags.c | 2 --
2 files changed, 6 deletions(-)
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 476026f82b32b..217431cf43413 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -241,10 +241,8 @@ static void getAArch64MultilibFlags(const Driver &D,
if (FeatureSet.contains("+strict-align")) {
Result.push_back("-mno-unaligned-access");
- Result.push_back("-mstrict-align");
} else {
Result.push_back("-munaligned-access");
- Result.push_back("-mno-strict-align");
}
if (Arg *Endian = Args.getLastArg(options::OPT_mbig_endian,
@@ -315,10 +313,8 @@ static void getARMMultilibFlags(const Driver &D,
if (FeatureSet.contains("+strict-align")) {
Result.push_back("-mno-unaligned-access");
- Result.push_back("-mstrict-align");
} else {
Result.push_back("-munaligned-access");
- Result.push_back("-mno-strict-align");
}
if (Arg *Endian = Args.getLastArg(options::OPT_mbig_endian,
diff --git a/clang/test/Driver/print-multi-selection-flags.c b/clang/test/Driver/print-multi-selection-flags.c
index ad44a5c3789ae..5f9383fbed8f4 100644
--- a/clang/test/Driver/print-multi-selection-flags.c
+++ b/clang/test/Driver/print-multi-selection-flags.c
@@ -74,14 +74,12 @@
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mno-unaligned-access | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mstrict-align | FileCheck --check-prefix=CHECK-NO-UNALIGNED-ACCESS %s
// CHECK-NO-UNALIGNED-ACCESS: -mno-unaligned-access
-// CHECK-NO-UNALIGNED-ACCESS: -mstrict-align
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mno-strict-align | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -munaligned-access | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -mno-strict-align | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=aarch64-none-elf -munaligned-access | FileCheck --check-prefix=CHECK-UNALIGNED-ACCESS %s
-// CHECK-UNALIGNED-ACCESS: -mno-strict-align
// CHECK-UNALIGNED-ACCESS: -munaligned-access
// RUN: %clang -multi-lib-config=%S/Inputs/multilib/empty.yaml -print-multi-flags-experimental --target=arm-none-eabi -mbig-endian | FileCheck --check-prefix=CHECK-BIG-ENDIAN %s
More information about the cfe-commits
mailing list