[llvm] r225596 - X86: teach X86TargetLowering about L, M, O constraints

[Saleem Abdulrasool]

Author: compnerd
Date: Sat Jan 10 22:39:24 2015
New Revision: 225596

URL: http://llvm.org/viewvc/llvm-project?rev=225596&view=rev
Log:
X86: teach X86TargetLowering about L,M,O constraints

Teach the ISelLowering for X86 about the L,M,O target specific constraints.
Although, for the moment, clang performs constraint validation and prevents
passing along inline asm which may have immediate constant constraints violated,
the backend should be able to cope with the invalid inline asm a bit better.

Added:
    llvm/trunk/test/CodeGen/X86/x86-inline-asm-validation.ll
Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=225596&r1=225595&r2=225596&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Sat Jan 10 22:39:24 2015
@@ -26255,12 +26255,37 @@ void X86TargetLowering::LowerAsmOperandF
       }
     }
     return;
+  case 'L':
+    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
+      if (C->getZExtValue() == 0xff || C->getZExtValue() == 0xffff ||
+          (Subtarget->is64Bit() && C->getZExtValue() == 0xffffffff)) {
+        Result = DAG.getTargetConstant(C->getSExtValue(), Op.getValueType());
+        break;
+      }
+    }
+    return;
+  case 'M':
+    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
+      if (C->getZExtValue() <= 3) {
+        Result = DAG.getTargetConstant(C->getZExtValue(), Op.getValueType());
+        break;
+      }
+    }
+    return;
   case 'N':
     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
       if (C->getZExtValue() <= 255) {
         Result = DAG.getTargetConstant(C->getZExtValue(), Op.getValueType());
         break;
       }
+    }
+    return;
+  case 'O':
+    if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op)) {
+      if (C->getZExtValue() <= 127) {
+        Result = DAG.getTargetConstant(C->getZExtValue(), Op.getValueType());
+        break;
+      }
     }
     return;
   case 'e': {

Added: llvm/trunk/test/CodeGen/X86/x86-inline-asm-validation.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/x86-inline-asm-validation.ll?rev=225596&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/x86-inline-asm-validation.ll (added)
+++ llvm/trunk/test/CodeGen/X86/x86-inline-asm-validation.ll Sat Jan 10 22:39:24 2015
@@ -0,0 +1,34 @@
+; RUN: llc -mtriple i686-gnu -filetype asm -o - %s 2>&1 | FileCheck %s
+
+define void @test_L_ff() {
+entry:
+  call void asm "", "L,~{dirflag},~{fpsr},~{flags}"(i32 255)
+  ret void
+}
+
+; CHECK-NOT: error: invalid operand for inline asm constraint 'L'
+
+define void @test_L_ffff() {
+entry:
+  call void asm "", "L,~{dirflag},~{fpsr},~{flags}"(i32 65535)
+  ret void
+}
+
+; CHECK-NOT: error: invalid operand for inline asm constraint 'L'
+
+define void @test_M_1() {
+entry:
+  call void asm "", "M,~{dirflag},~{fpsr},~{flags}"(i32 1)
+  ret void
+}
+
+; CHECK-NOT: error: invalid operand for inline asm constraint 'M'
+
+define void @test_O_64() {
+entry:
+  call void asm "", "O,~{dirflag},~{fpsr},~{flags}"(i32 64)
+  ret void
+}
+
+; CHECK-NOT: error: invalid operand for inline asm constraint 'O'
+