X86: Support dollar symbol for AT&T syntax and add output-asm-variant to llc #147876
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@llvm/pr-subscribers-backend-x86 Author: Fangrui Song (MaskRay) Changes'$' indicates immediate values in AT&T syntax, so symbol names starting Add Note: In these positions the symbol name cannot be quoted: Close #147587 Full diff: https://github.com/llvm/llvm-project/pull/147876.diff 6 Files Affected:
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.cpp
index 6614eea3901bd..564636959f00f 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.cpp
@@ -14,6 +14,7 @@
#include "X86ATTInstPrinter.h"
#include "X86BaseInfo.h"
#include "X86InstComments.h"
+#include "llvm/ADT/SmallString.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
@@ -35,6 +36,21 @@ using namespace llvm;
#define PRINT_ALIAS_INSTR
#include "X86GenAsmWriter.inc"
+// Print an MCExpr as an operand. Similar to GCC, wrap the output in parentheses
+// if it begins with '$', as '$' in an operand position indicates an immediate
+// value in the AT&T syntax.
+void X86ATTInstPrinter::printExprOperand(raw_ostream &OS, const MCExpr &E) {
+ SmallString<128> S;
+ {
+ raw_svector_ostream SOS(S);
+ MAI.printExpr(SOS, E);
+ }
+ if (S.starts_with("$"))
+ OS << '(' << S << ')';
+ else
+ OS << S;
+}
+
void X86ATTInstPrinter::printRegName(raw_ostream &OS, MCRegister Reg) {
markup(OS, Markup::Register) << '%' << getRegisterName(Reg);
}
@@ -446,7 +462,7 @@ void X86ATTInstPrinter::printMemReference(const MCInst *MI, unsigned Op,
O << formatImm(DispVal);
} else {
assert(DispSpec.isExpr() && "non-immediate displacement for LEA?");
- MAI.printExpr(O, *DispSpec.getExpr());
+ printExprOperand(O, *DispSpec.getExpr());
}
if (IndexReg.getReg() || BaseReg.getReg()) {
@@ -501,7 +517,7 @@ void X86ATTInstPrinter::printMemOffset(const MCInst *MI, unsigned Op,
O << formatImm(DispSpec.getImm());
} else {
assert(DispSpec.isExpr() && "non-immediate displacement?");
- MAI.printExpr(O, *DispSpec.getExpr());
+ printExprOperand(O, *DispSpec.getExpr());
}
}
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.h b/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.h
index f49f09c5dcf3e..1452622ebcea8 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.h
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86ATTInstPrinter.h
@@ -23,6 +23,7 @@ class X86ATTInstPrinter final : public X86InstPrinterCommon {
const MCRegisterInfo &MRI)
: X86InstPrinterCommon(MAI, MII, MRI), HasCustomInstComment(false) {}
+ void printExprOperand(raw_ostream &OS, const MCExpr &E) override;
void printRegName(raw_ostream &OS, MCRegister Reg) override;
void printInst(const MCInst *MI, uint64_t Address, StringRef Annot,
const MCSubtargetInfo &STI, raw_ostream &OS) override;
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.cpp
index 7523d2aedcced..1c5f1663d4f52 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.cpp
@@ -26,6 +26,10 @@
using namespace llvm;
+void X86InstPrinterCommon::printExprOperand(raw_ostream &OS, const MCExpr &E) {
+ MAI.printExpr(OS, E);
+}
+
void X86InstPrinterCommon::printCondCode(const MCInst *MI, unsigned Op,
raw_ostream &O) {
int64_t Imm = MI->getOperand(Op).getImm();
@@ -374,7 +378,7 @@ void X86InstPrinterCommon::printPCRelImm(const MCInst *MI, uint64_t Address,
markup(O, Markup::Immediate) << formatHex((uint64_t)Address);
} else {
// Otherwise, just print the expression.
- MAI.printExpr(O, *Op.getExpr());
+ printExprOperand(O, *Op.getExpr());
}
}
}
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.h b/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.h
index 2a7b750bd6752..2c9467ca7c615 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.h
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86InstPrinterCommon.h
@@ -17,11 +17,13 @@
#include "llvm/MC/MCInstPrinter.h"
namespace llvm {
+class MCExpr;
class X86InstPrinterCommon : public MCInstPrinter {
public:
using MCInstPrinter::MCInstPrinter;
+ virtual void printExprOperand(raw_ostream &OS, const MCExpr &E);
virtual void printOperand(const MCInst *MI, unsigned OpNo, raw_ostream &O) = 0;
void printCondCode(const MCInst *MI, unsigned Op, raw_ostream &OS);
void printCondFlags(const MCInst *MI, unsigned Op, raw_ostream &OS);
diff --git a/llvm/test/CodeGen/X86/dollar-name.ll b/llvm/test/CodeGen/X86/dollar-name.ll
index fc9d6a77f66e5..ffa03fc1f6f9a 100644
--- a/llvm/test/CodeGen/X86/dollar-name.ll
+++ b/llvm/test/CodeGen/X86/dollar-name.ll
@@ -1,18 +1,78 @@
-; RUN: llc < %s -mtriple=i386-linux | FileCheck %s
-; PR1339
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=i686 -relocation-model=static | FileCheck %s --check-prefix=STATIC
+; RUN: llc < %s -mtriple=x86_64 -relocation-model=pic | FileCheck %s --check-prefix=PIC
+; RUN: llc < %s -mtriple=x86_64 -relocation-model=pic -output-asm-variant=1 | FileCheck %s --check-prefix=INTEL-PIC
-@"$bar" = global i32 zeroinitializer
+@"$arr" = global [2 x i32] zeroinitializer
+@"$arr_h" = hidden global [2 x i32] zeroinitializer
@"$qux" = external dso_local global i32
+@"$tls" = hidden thread_local global i32 0
define i32 @"$foo"() nounwind {
-; CHECK: movl $bar,
-; CHECK: addl $qux,
-; CHECK: calll $hen
- %m = load i32, ptr @"$bar"
+; STATIC-LABEL: $foo:
+; STATIC: # %bb.0:
+; STATIC-NEXT: movl ($arr), %eax
+; STATIC-NEXT: movl %gs:0, %ecx
+; STATIC-NEXT: addl ($arr+4), %eax
+; STATIC-NEXT: addl ($qux), %eax
+; STATIC-NEXT: addl ($tls@NTPOFF)(%ecx), %eax
+; STATIC-NEXT: pushl ($arr_h)
+; STATIC-NEXT: pushl %eax
+; STATIC-NEXT: calll ($hen@PLT)
+; STATIC-NEXT: addl $8, %esp
+; STATIC-NEXT: retl
+;
+; PIC-LABEL: $foo:
+; PIC: # %bb.0:
+; PIC-NEXT: pushq %rbp
+; PIC-NEXT: pushq %r14
+; PIC-NEXT: pushq %rbx
+; PIC-NEXT: movq ($arr@GOTPCREL)(%rip), %r14
+; PIC-NEXT: movl (%r14), %ebx
+; PIC-NEXT: movl ($arr_h)(%rip), %ebp
+; PIC-NEXT: leaq ($tls@TLSLD)(%rip), %rdi
+; PIC-NEXT: callq __tls_get_addr@PLT
+; PIC-NEXT: addl 4(%r14), %ebx
+; PIC-NEXT: addl ($qux)(%rip), %ebx
+; PIC-NEXT: addl ($tls@DTPOFF)(%rax), %ebx
+; PIC-NEXT: movl %ebx, %edi
+; PIC-NEXT: movl %ebp, %esi
+; PIC-NEXT: callq ($hen@PLT)
+; PIC-NEXT: popq %rbx
+; PIC-NEXT: popq %r14
+; PIC-NEXT: popq %rbp
+; PIC-NEXT: retq
+;
+; INTEL-PIC-LABEL: $foo:
+; INTEL-PIC: # %bb.0:
+; INTEL-PIC-NEXT: push rbp
+; INTEL-PIC-NEXT: push r14
+; INTEL-PIC-NEXT: push rbx
+; INTEL-PIC-NEXT: mov r14, qword ptr [rip + $arr@GOTPCREL]
+; INTEL-PIC-NEXT: mov ebx, dword ptr [r14]
+; INTEL-PIC-NEXT: mov ebp, dword ptr [rip + $arr_h]
+; INTEL-PIC-NEXT: lea rdi, [rip + $tls@TLSLD]
+; INTEL-PIC-NEXT: call __tls_get_addr@PLT
+; INTEL-PIC-NEXT: add ebx, dword ptr [r14 + 4]
+; INTEL-PIC-NEXT: add ebx, dword ptr [rip + $qux]
+; INTEL-PIC-NEXT: add ebx, dword ptr [rax + $tls@DTPOFF]
+; INTEL-PIC-NEXT: mov edi, ebx
+; INTEL-PIC-NEXT: mov esi, ebp
+; INTEL-PIC-NEXT: call $hen@PLT
+; INTEL-PIC-NEXT: pop rbx
+; INTEL-PIC-NEXT: pop r14
+; INTEL-PIC-NEXT: pop rbp
+; INTEL-PIC-NEXT: ret
+ %m = load i32, ptr @"$arr"
+ %m1 = load i32, ptr getelementptr inbounds nuw (i32, ptr @"$arr", i23 1)
+ %m2 = load i32, ptr @"$arr_h"
%n = load i32, ptr @"$qux"
- %t = add i32 %m, %n
- %u = call i32 @"$hen"(i32 %t)
+ %tls_v = load i32, ptr @"$tls"
+ %t0 = add i32 %m, %m1
+ %t1 = add i32 %t0, %n
+ %t2 = add i32 %t1, %tls_v
+ %u = call i32 @"$hen"(i32 %t2, i32 %m2)
ret i32 %u
}
-declare i32 @"$hen"(i32 %a)
+declare i32 @"$hen"(i32 %a, i32 %b)
diff --git a/llvm/tools/llc/llc.cpp b/llvm/tools/llc/llc.cpp
index 140459ba2de21..93b4a50ef86d7 100644
--- a/llvm/tools/llc/llc.cpp
+++ b/llvm/tools/llc/llc.cpp
@@ -143,6 +143,10 @@ static cl::opt<bool>
static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
cl::desc("Show encoding in .s output"));
+static cl::opt<unsigned>
+ OutputAsmVariant("output-asm-variant",
+ cl::desc("Syntax variant to use for output printing"));
+
static cl::opt<bool>
DwarfDirectory("dwarf-directory", cl::Hidden,
cl::desc("Use .file directives with an explicit directory"),
@@ -500,6 +504,8 @@ static int compileModule(char **argv, LLVMContext &Context) {
Options.MCOptions.ShowMCEncoding = ShowMCEncoding;
Options.MCOptions.AsmVerbose = AsmVerbose;
Options.MCOptions.PreserveAsmComments = PreserveComments;
+ if (OutputAsmVariant.getNumOccurrences())
+ Options.MCOptions.OutputAsmVariant = OutputAsmVariant;
Options.MCOptions.IASSearchPaths = IncludeDirs;
Options.MCOptions.InstPrinterOptions = InstPrinterOptions;
Options.MCOptions.SplitDwarfFile = SplitDwarfFile;
|
| ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5 | ||
| ; RUN: llc < %s -mtriple=i686 -relocation-model=static | FileCheck %s --check-prefix=STATIC | ||
| ; RUN: llc < %s -mtriple=x86_64 -relocation-model=pic | FileCheck %s --check-prefix=PIC | ||
| ; RUN: llc < %s -mtriple=x86_64 -relocation-model=pic -output-asm-variant=1 | FileCheck %s --check-prefix=INTEL-PIC |
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Can we use --x86-asm-syntax=intel instead?
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Oh, I saw the reason in description now.
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--x86-asm-syntax=intel modifies X86MCAsmInfo, affecting both assembly input and output. I think we should migrate the assembly output part to -output-asm-variant #109360
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But we don't have inline assemble in the test. Does it matter here?
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Added module asm "mov ($foo), %eax" to dollar-name-asm.ll. It demonstrates that -x86-asm-syntax=intel cannot be used.
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You didn't add that file :)
I think that doesn't matter since we only care about the |
In the Intel syntax, |
|
In your commit I suspect this will not be correct: As said earlier the at&t syntax is just nonsense like in |
Both
Both In MC, $a+16 is encoded as: To handle this and deeper nesting, the PR uses a straightforward approach that checks if the output begins with |
Have you tried the FreeBSD assembler, or the Solaris one? |
No. I vaguely recall that older versions of FreeBSD used an ancient GPL 2 binutils. I believe this |
Created using spr 1.3.5-bogner
Created using spr 1.3.5-bogner
MaskRay
deleted the
users/MaskRay/spr/x86-support-dollar-symbol-for-att-syntax-and-add-output-asm-variant-to-llc
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…asm-variant to llc '$' indicates immediate values in AT&T syntax, so symbol names starting with '$' need to be quoted or wrapped in parentheses. Parentheses are preferred to support expressions with relocation specifiers without modifying MCExpr internals, aligning with GCC (https://gcc.gnu.org/PR91298). Add `-output-asm-variant` to llc for testing Intel syntax, avoiding `-x86-asm-syntax` which affects MCAsmInfo used by input assembly (-x86-asm-syntax=intel doesn't work with AT&T module asm) Note: In these positions the symbol name cannot be quoted: `$var:` `.globl $var` `.type $var, @object` Close #147587 Pull Request: llvm/llvm-project#147876
'$' indicates immediate values in AT&T syntax, so symbol names starting
with '$' need to be quoted or wrapped in parentheses. Parentheses are
preferred to support expressions with relocation specifiers without
modifying MCExpr internals, aligning with GCC (https://gcc.gnu.org/PR91298).
Add
-output-asm-variantto llc for testing Intel syntax, avoiding-x86-asm-syntaxwhich affects MCAsmInfo used by input assembly(-x86-asm-syntax=intel doesn't work with AT&T module asm)
Note: In these positions the symbol name cannot be quoted:
$var:.globl $var.type $var, @objectClose #147587