[libc-commits] [libc] [clang-tools-extra] [lld] [lldb] [clang] [libcxx] [flang] [llvm] [AArch64] Support optional constant offset for constraint "S" (PR #80255)
Fangrui Song via libc-commits
libc-commits at lists.llvm.org
Fri Feb 2 09:37:11 PST 2024
https://github.com/MaskRay updated https://github.com/llvm/llvm-project/pull/80255
>From 8ce25b59ac48e3b0a69c28e8af3abe6d7cbf0c42 Mon Sep 17 00:00:00 2001
From: Fangrui Song <i at maskray.me>
Date: Wed, 31 Jan 2024 23:25:23 -0800
Subject: [PATCH] =?UTF-8?q?[=F0=9D=98=80=F0=9D=97=BD=F0=9D=97=BF]=20initia?=
=?UTF-8?q?l=20version?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Created using spr 1.3.4
---
clang/test/Sema/inline-asm-validate-aarch64.c | 17 ++++++++++++++---
llvm/docs/LangRef.rst | 2 ++
.../Target/AArch64/AArch64ISelLowering.cpp | 19 ++++++-------------
.../CodeGen/AArch64/inlineasm-S-constraint.ll | 4 ++++
.../CodeGen/RISCV/inline-asm-S-constraint.ll | 1 +
5 files changed, 27 insertions(+), 16 deletions(-)
diff --git a/clang/test/Sema/inline-asm-validate-aarch64.c b/clang/test/Sema/inline-asm-validate-aarch64.c
index 014767d5a3923..1e753d40d8ca0 100644
--- a/clang/test/Sema/inline-asm-validate-aarch64.c
+++ b/clang/test/Sema/inline-asm-validate-aarch64.c
@@ -1,14 +1,24 @@
+// RUN: %clang_cc1 -triple aarch64 -fsyntax-only -verify -DVERIFY %s
// RUN: %clang_cc1 -triple arm64-apple-darwin -fsyntax-only -fdiagnostics-parseable-fixits %s 2>&1 | FileCheck %s
typedef unsigned char uint8_t;
+#ifdef VERIFY
+void test_s(int i) {
+ asm("" :: "s"(i)); // expected-error{{invalid input constraint 's' in asm}}
+
+ /// Codegen error
+ asm("" :: "S"(i));
+ asm("" :: "S"(test_s(i))); // expected-error{{invalid type 'void' in asm input for constraint 'S'}}
+}
+#else
uint8_t constraint_r(uint8_t *addr) {
uint8_t byte;
__asm__ volatile("ldrb %0, [%1]" : "=r" (byte) : "r" (addr) : "memory");
// CHECK: warning: value size does not match register size specified by the constraint and modifier
// CHECK: note: use constraint modifier "w"
-// CHECK: fix-it:{{.*}}:{8:26-8:28}:"%w0"
+// CHECK: fix-it:{{.*}}:{[[#@LINE-3]]:26-[[#@LINE-3]]:28}:"%w0"
return byte;
}
@@ -19,7 +29,7 @@ uint8_t constraint_r_symbolic(uint8_t *addr) {
__asm__ volatile("ldrb %[s0], [%[s1]]" : [s0] "=r" (byte) : [s1] "r" (addr) : "memory");
// CHECK: warning: value size does not match register size specified by the constraint and modifier
// CHECK: note: use constraint modifier "w"
-// CHECK: fix-it:{{.*}}:{19:26-19:31}:"%w[s0]"
+// CHECK: fix-it:{{.*}}:{[[#@LINE-3]]:26-[[#@LINE-3]]:31}:"%w[s0]"
return byte;
}
@@ -40,11 +50,11 @@ uint8_t constraint_r_symbolic_macro(uint8_t *addr) {
// CHECK: warning: value size does not match register size specified by the constraint and modifier
// CHECK: asm ("%w0 %w1 %2" : "+r" (one) : "r" (wide_two));
// CHECK: note: use constraint modifier "w"
-// CHECK: fix-it:{{.*}}:{47:17-47:19}:"%w2"
void read_write_modifier0(int one, int two) {
long wide_two = two;
asm ("%w0 %w1 %2" : "+r" (one) : "r" (wide_two));
+// CHECK: fix-it:{{.*}}:{[[#@LINE-1]]:17-[[#@LINE-1]]:19}:"%w2"
}
// CHECK-NOT: warning:
@@ -52,3 +62,4 @@ void read_write_modifier1(int one, int two) {
long wide_two = two;
asm ("%w0 %1" : "+r" (one), "+r" (wide_two));
}
+#endif
diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
index 7a7ddc59ba985..b13f8c7811d16 100644
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -5107,6 +5107,8 @@ AArch64:
offsets). (However, LLVM currently does this for the ``m`` constraint as
well.)
- ``r``: A 32 or 64-bit integer register (W* or X*).
+- ``S``: A symbol or label reference with a constant offset. The generic ``s``
+ is not supported.
- ``Uci``: Like r, but restricted to registers 8 to 11 inclusive.
- ``Ucj``: Like r, but restricted to registers 12 to 15 inclusive.
- ``w``: A 32, 64, or 128-bit floating-point, SIMD or SVE vector register.
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index bb19aef978b94..62f160c1c33fc 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -10618,7 +10618,7 @@ AArch64TargetLowering::getConstraintType(StringRef Constraint) const {
case 'Z':
return C_Immediate;
case 'z':
- case 'S': // A symbolic address
+ case 'S': // A symbol or label reference with a constant offset
return C_Other;
}
} else if (parsePredicateConstraint(Constraint))
@@ -10801,19 +10801,12 @@ void AArch64TargetLowering::LowerAsmOperandForConstraint(
Result = DAG.getRegister(AArch64::WZR, MVT::i32);
break;
}
- case 'S': {
- // An absolute symbolic address or label reference.
- if (const GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(Op)) {
- Result = DAG.getTargetGlobalAddress(GA->getGlobal(), SDLoc(Op),
- GA->getValueType(0));
- } else if (const BlockAddressSDNode *BA =
- dyn_cast<BlockAddressSDNode>(Op)) {
- Result =
- DAG.getTargetBlockAddress(BA->getBlockAddress(), BA->getValueType(0));
- } else
- return;
+ case 'S':
+ // Use the generic code path for "s". In GCC's aarch64 port, "S" is
+ // supported for PIC while "s" isn't, making "s" less useful. We implement
+ // "S" but not "s".
+ TargetLowering::LowerAsmOperandForConstraint(Op, "s", Ops, DAG);
break;
- }
case 'I':
case 'J':
diff --git a/llvm/test/CodeGen/AArch64/inlineasm-S-constraint.ll b/llvm/test/CodeGen/AArch64/inlineasm-S-constraint.ll
index 18b4ef955236a..7664ad16dd568 100644
--- a/llvm/test/CodeGen/AArch64/inlineasm-S-constraint.ll
+++ b/llvm/test/CodeGen/AArch64/inlineasm-S-constraint.ll
@@ -1,11 +1,15 @@
;RUN: llc -mtriple=aarch64-none-linux-gnu -mattr=+neon < %s | FileCheck %s
@var = global i32 0
+ at a = external global [2 x [2 x i32]], align 4
+
define void @test_inline_constraint_S() {
; CHECK-LABEL: test_inline_constraint_S:
call void asm sideeffect "adrp x0, $0", "S"(ptr @var)
call void asm sideeffect "add x0, x0, :lo12:$0", "S"(ptr @var)
+ call void asm sideeffect "// $0", "S"(ptr getelementptr inbounds ([2 x [2 x i32]], ptr @a, i64 0, i64 1, i64 1))
; CHECK: adrp x0, var
; CHECK: add x0, x0, :lo12:var
+; CHECK: // a+12
ret void
}
define i32 @test_inline_constraint_S_label(i1 %in) {
diff --git a/llvm/test/CodeGen/RISCV/inline-asm-S-constraint.ll b/llvm/test/CodeGen/RISCV/inline-asm-S-constraint.ll
index 11add36da27b6..a54cc3c14e741 100644
--- a/llvm/test/CodeGen/RISCV/inline-asm-S-constraint.ll
+++ b/llvm/test/CodeGen/RISCV/inline-asm-S-constraint.ll
@@ -3,6 +3,7 @@
; RUN: llc -mtriple=riscv64 < %s | FileCheck %s --check-prefix=RV64
@var = external dso_local global i32, align 4
+ at a = external global [2 x [2 x i32]], align 4
define dso_local ptr @constraint_S() {
; RV32-LABEL: constraint_S:
More information about the libc-commits
mailing list