[ms-inline-asm][AVX512] Add ability to use k registers in MS inline asm + fix bag with curly braces

[myatsina]

Summary

Until now curly braces could only be used in MS inline assembly to mark block start/end.
All curly braces were removed completely at a very early stage.
This approach caused bugs like:
"m{o}v eax, ebx" turned into "mov eax, ebx" without any error.

In addition, AVX-512 added special operands (e.g., k registers), which are also surrounded by curly braces that mark them as such.
Now, we need to keep the curly braces and identify at a later stage if they are marking block start/end (if so, ignore them), or surrounding special AVX-512 operands (if so, parse them as such).

This patch fixes the bug described above and enables the use of AVX-512 special operands.

This review is for the clang part.
The llvm part of the review is: http://reviews.llvm.org/D17767

[• ehsan]

LGTM.

lib/Parse/ParseStmtAsm.cpp

446

Nit: *brace

[myatsina]

Updated test to reflect changes in the llvm part of the review (http://reviews.llvm.org/D17767)

lib/Parse/ParseStmtAsm.cpp

StmtResult Parser::ParseMicrosoftAsmStatement(SourceLocation AsmLoc) {
   do {
     // If we hit EOF, we're done, period.
     if (isEofOrEom())
       break;
 
     if (!InAsmComment && Tok.is(tok::l_brace)) {
       // Consume the opening brace.
       SkippedStartOfLine = Tok.isAtStartOfLine();
+      AsmToks.push_back(Tok);
       EndLoc = ConsumeBrace();
       BraceNesting++;
       LBraceLocs.push_back(EndLoc);
       TokLoc = Tok.getLocation();
       ++NumTokensRead;
       continue;
     } else if (!InAsmComment && Tok.is(tok::semi)) {
       // A semicolon in an asm is the start of a comment.
if (!InAsmComment && Tok.is(tok::l_brace)) {
         if (!BraceNesting)
           break;
       }
     }
     if (!InAsmComment && BraceNesting && Tok.is(tok::r_brace) &&
         BraceCount == (savedBraceCount + BraceNesting)) {
       // Consume the closing brace.
       SkippedStartOfLine = Tok.isAtStartOfLine();
+      // Don't want to add the closing brace of the whole asm block
+      if (SingleLineMode || BraceNesting > 1) {
+        Tok.clearFlag(Token::LeadingSpace);
+        AsmToks.push_back(Tok);
+      }
       EndLoc = ConsumeBrace();
       BraceNesting--;
       // Finish if all of the opened braces in the inline asm section were
       // consumed.
       if (BraceNesting == 0 && !SingleLineMode)
         break;
       else {
         LBraceLocs.pop_back();

test/CodeGen/ms-inline-asm-avx512.c

 // REQUIRES: x86-registered-target
 // RUN: %clang_cc1 %s -triple x86_64-pc-windows-msvc -target-cpu knl -fasm-blocks -emit-llvm -o - | FileCheck %s
 
 void t1() {
 // CHECK: @t1
 // CHECK: call void asm sideeffect inteldialect "vaddpd zmm8, zmm27, zmm6", "~{zmm8},~{dirflag},~{fpsr},~{flags}"()
 // CHECK: ret void
   __asm {
     vaddpd zmm8, zmm27, zmm6
   }
 }
+
+
+void t2() {
+// CHECK: @t2
+// CHECK: call void asm sideeffect inteldialect "vaddpd zmm8 {k1}, zmm27, zmm6", "~{zmm8},~{dirflag},~{fpsr},~{flags}"()
+// CHECK: ret void
+  __asm {
+    vaddpd zmm8 {k1}, zmm27, zmm6
+  }
+}

test/CodeGen/ms-inline-asm.c

 
 void t9() {
   __asm {
     push ebx
     { mov ebx, 0x07 }
     __asm { pop ebx }
   }
 // CHECK: t9
-// CHECK: call void asm sideeffect inteldialect "push ebx\0A\09mov ebx, $$0x07\0A\09pop ebx", "~{ebx},~{esp},~{dirflag},~{fpsr},~{flags}"()
+// CHECK: call void asm sideeffect inteldialect "push ebx\0A\09mov ebx, $$0x07\0A\09pop ebx\0A\09", "~{ebx},~{esp},~{dirflag},~{fpsr},~{flags}"()
 }
 
 unsigned t10(void) {
   unsigned i = 1, j;
   __asm {
     mov eax, i
     mov j, eax
   }

test/Parser/ms-inline-asm.c

void t10() {
   }
 }
 void t11() {
   do { __asm mov eax, 0 __asm { __asm mov edx, 1 } } while(0);
 }
 void t12() {
   __asm jmp label // expected-error {{use of undeclared label 'label'}}
 }
+void t13() {
+  __asm m{o}v eax, ebx // expected-error {{expected identifier}} expected-error {{use of undeclared label '{o}v eax, ebx'}}
+}
+
 int t_fail() { // expected-note {{to match this}}
   __asm 
   __asm { // expected-error 3 {{expected}} expected-note {{to match this}}