[llvm-commits] [llvm] r172228 - in /llvm/trunk: lib/CodeGen/MachineInstr.cpp lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp lib/CodeGen/SelectionDAG/TargetLowering.cpp test/CodeGen/Generic/inline-asm-mem-clobber.ll

[Eric Christopher]

Author: echristo
Date: Fri Jan 11 12:12:39 2013
New Revision: 172228

URL: http://llvm.org/viewvc/llvm-project?rev=172228&view=rev
Log:
For inline asm:

- recognize string "{memory}" in the MI generation
- mark as mayload/maystore when there's a memory clobber constraint.

PR14859.

Patch by Krzysztof Parzyszek

Added:
    llvm/trunk/test/CodeGen/Generic/inline-asm-mem-clobber.ll
Modified:
    llvm/trunk/lib/CodeGen/MachineInstr.cpp
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
    llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp

Modified: llvm/trunk/lib/CodeGen/MachineInstr.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineInstr.cpp?rev=172228&r1=172227&r2=172228&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/MachineInstr.cpp (original)
+++ llvm/trunk/lib/CodeGen/MachineInstr.cpp Fri Jan 11 12:12:39 2013
@@ -1476,10 +1476,14 @@
     OS << " ";
     getOperand(InlineAsm::MIOp_AsmString).print(OS, TM);
 
-    // Print HasSideEffects, IsAlignStack
+    // Print HasSideEffects, MayLoad, MayStore, IsAlignStack
     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
       OS << " [sideeffect]";
+    if (ExtraInfo & InlineAsm::Extra_MayLoad)
+      OS << " [mayload]";
+    if (ExtraInfo & InlineAsm::Extra_MayStore)
+      OS << " [maystore]";
     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
       OS << " [alignstack]";
     if (getInlineAsmDialect() == InlineAsm::AD_ATT)

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp?rev=172228&r1=172227&r2=172228&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp Fri Jan 11 12:12:39 2013
@@ -5948,6 +5948,10 @@
     // Compute the constraint code and ConstraintType to use.
     TLI.ComputeConstraintToUse(OpInfo, OpInfo.CallOperand, &DAG);
 
+    if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
+        OpInfo.Type == InlineAsm::isClobber)
+      continue;
+
     // If this is a memory input, and if the operand is not indirect, do what we
     // need to to provide an address for the memory input.
     if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
@@ -6051,6 +6055,8 @@
         ExtraInfo |= InlineAsm::Extra_MayLoad;
       else if (OpInfo.Type == InlineAsm::isOutput)
         ExtraInfo |= InlineAsm::Extra_MayStore;
+      else if (OpInfo.Type == InlineAsm::isClobber)
+        ExtraInfo |= (InlineAsm::Extra_MayLoad | InlineAsm::Extra_MayStore);
     }
   }
 

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp?rev=172228&r1=172227&r2=172228&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp Fri Jan 11 12:12:39 2013
@@ -3068,7 +3068,9 @@
 
 TargetLowering::ConstraintType
 TargetLowering::getConstraintType(const std::string &Constraint) const {
-  if (Constraint.size() == 1) {
+  unsigned S = Constraint.size();
+
+  if (S == 1) {
     switch (Constraint[0]) {
     default: break;
     case 'r': return C_RegisterClass;
@@ -3097,9 +3099,11 @@
     }
   }
 
-  if (Constraint.size() > 1 && Constraint[0] == '{' &&
-      Constraint[Constraint.size()-1] == '}')
+  if (S > 1 && Constraint[0] == '{' && Constraint[S-1] == '}') {
+    if (S == 8 && !Constraint.compare(1, 6, "memory", 6))  // "{memory}"
+      return C_Memory;
     return C_Register;
+  }
   return C_Unknown;
 }
 

Added: llvm/trunk/test/CodeGen/Generic/inline-asm-mem-clobber.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Generic/inline-asm-mem-clobber.ll?rev=172228&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Generic/inline-asm-mem-clobber.ll (added)
+++ llvm/trunk/test/CodeGen/Generic/inline-asm-mem-clobber.ll Fri Jan 11 12:12:39 2013
@@ -0,0 +1,21 @@
+; RUN: llc -O2 < %s | FileCheck %s
+
+ at G = common global i32 0, align 4
+
+define i32 @foo(i8* %p) nounwind uwtable {
+entry:
+  %p.addr = alloca i8*, align 8
+  %rv = alloca i32, align 4
+  store i8* %p, i8** %p.addr, align 8
+  store i32 0, i32* @G, align 4
+  %0 = load i8** %p.addr, align 8
+; CHECK: blah
+  %1 = call i32 asm "blah", "=r,r,~{memory}"(i8* %0) nounwind
+; CHECK: @G
+  store i32 %1, i32* %rv, align 4
+  %2 = load i32* %rv, align 4
+  %3 = load i32* @G, align 4
+  %add = add nsw i32 %2, %3
+  ret i32 %add
+}
+