[llvm] 3d38a97 - [X86] Parse data32 call in .code16 as CALLpcrel32

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2020-09-23T18:37:41-07:00
New Revision: 3d38a975d72c8711a123d1862e517bcbdab7d700

URL: https://github.com/llvm/llvm-project/commit/3d38a975d72c8711a123d1862e517bcbdab7d700
DIFF: https://github.com/llvm/llvm-project/commit/3d38a975d72c8711a123d1862e517bcbdab7d700.diff

LOG: [X86] Parse data32 call in .code16 as CALLpcrel32

Used by kexec-tools (PR46942)
In GNU as, tc-i386.c:output_jump uses 4-byte immediate if a data32 prefix is present.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D88137

Added: 
    

Modified: 
    llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
    llvm/test/MC/X86/data-prefix-fail.s
    llvm/test/MC/X86/x86-16.s

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
index 3270932a76d0..2b48d4bd8abe 100644
--- a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -3012,6 +3012,17 @@ bool X86AsmParser::ParseInstruction(ParseInstructionInfo &Info, StringRef Name,
       return Error(NameLoc, "'data32' is not supported in 64-bit mode");
     // Hack to 'data16' for the table lookup.
     PatchedName = "data16";
+
+    if (getLexer().isNot(AsmToken::EndOfStatement)) {
+      StringRef Next = Parser.getTok().getString();
+      // Parse data32 call as calll.
+      if (Next == "call" || Next == "callw") {
+        getLexer().Lex();
+        Name = "calll";
+        PatchedName = Name;
+        isPrefix = false;
+      }
+    }
   }
 
   Operands.push_back(X86Operand::CreateToken(PatchedName, NameLoc));

diff  --git a/llvm/test/MC/X86/data-prefix-fail.s b/llvm/test/MC/X86/data-prefix-fail.s
index 1d2b528a4518..638e972ad478 100644
--- a/llvm/test/MC/X86/data-prefix-fail.s
+++ b/llvm/test/MC/X86/data-prefix-fail.s
@@ -23,3 +23,10 @@ data32 lgdt 0
 // 32: encoding: [0x0f,0x01,0x15,0x00,0x00,0x00,0x00]
 // ERR16: error: redundant data16 prefix
 data16 lgdt 0
+
+// 64:      data16    # encoding: [0x66]
+// 64-NEXT: callq  0  # encoding: [0xe8,A,A,A,A]
+// 32:      data16    # encoding: [0x66]
+// 32-NEXT: calll  0  # encoding: [0xe8,A,A,A,A]
+// ERR16: {{.*}}.s:[[#@LINE+1]]:1: error: redundant data16 prefix
+data16 call 0

diff  --git a/llvm/test/MC/X86/x86-16.s b/llvm/test/MC/X86/x86-16.s
index f1b4428703f1..277d8a010358 100644
--- a/llvm/test/MC/X86/x86-16.s
+++ b/llvm/test/MC/X86/x86-16.s
@@ -546,8 +546,12 @@ lcall	$0x7ace,$0x7ace
 jmp	$0x7ace,$0x7ace
 ljmp	$0x7ace,$0x7ace
 
+// CHECK: calll a
+// CHECK: calll a
 // CHECK: calll a
  calll a
+data32 call a
+data32 callw a
 
 // CHECK:	incb	%al # encoding: [0xfe,0xc0]
 	incb %al