[llvm-commits] [llvm] r41479 - in /llvm/trunk: lib/Target/X86/X86ISelLowering.cpp test/CodeGen/X86/2004-02-12-Memcpy.llx

[Rafael Espindola]

Author: rafael
Date: Mon Aug 27 05:18:20 2007
New Revision: 41479

URL: http://llvm.org/viewvc/llvm-project?rev=41479&view=rev
Log:
call libc memcpy/memset if array size is bigger then threshold.

Coping 100MB array (after a warmup) shows that glibc 2.6.1 implementation on
x86-64 (core 2) is 30% faster (from 0.270917s to 0.188079s)


Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/2004-02-12-Memcpy.llx

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=41479&r1=41478&r2=41479&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Mon Aug 27 05:18:20 2007
@@ -3753,10 +3753,10 @@
   if (Align == 0) Align = 1;
 
   ConstantSDNode *I = dyn_cast<ConstantSDNode>(Op.getOperand(3));
-  // If not DWORD aligned, call memset if size is less than the threshold.
+  // If not DWORD aligned or size is more than the threshold, call memset.
   // It knows how to align to the right boundary first.
   if ((Align & 3) != 0 ||
-      (I && I->getValue() < Subtarget->getMinRepStrSizeThreshold())) {
+      (I && I->getValue() > Subtarget->getMinRepStrSizeThreshold())) {
     MVT::ValueType IntPtr = getPointerTy();
     const Type *IntPtrTy = getTargetData()->getIntPtrType();
     TargetLowering::ArgListTy Args; 
@@ -3909,10 +3909,10 @@
   if (Align == 0) Align = 1;
 
   ConstantSDNode *I = dyn_cast<ConstantSDNode>(Op.getOperand(3));
-  // If not DWORD aligned, call memcpy if size is less than the threshold.
+  // If not DWORD aligned or size is more than the threshold, call memcpy.
   // It knows how to align to the right boundary first.
   if ((Align & 3) != 0 ||
-      (I && I->getValue() < Subtarget->getMinRepStrSizeThreshold())) {
+      (I && I->getValue() > Subtarget->getMinRepStrSizeThreshold())) {
     MVT::ValueType IntPtr = getPointerTy();
     TargetLowering::ArgListTy Args;
     TargetLowering::ArgListEntry Entry;

Modified: llvm/trunk/test/CodeGen/X86/2004-02-12-Memcpy.llx
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2004-02-12-Memcpy.llx?rev=41479&r1=41478&r2=41479&view=diff

==============================================================================
--- llvm/trunk/test/CodeGen/X86/2004-02-12-Memcpy.llx (original)
+++ llvm/trunk/test/CodeGen/X86/2004-02-12-Memcpy.llx Mon Aug 27 05:18:20 2007
@@ -1,24 +1,26 @@
-; RUN: llvm-upgrade < %s | llvm-as | llc -march=x86 | grep movs
-declare void %llvm.memcpy.i32(sbyte* %A, sbyte* %B, uint %amt, uint %align)
+; RUN: llvm-as < %s | llc -march=x86 | grep movs | count 1
+; RUN: llvm-as < %s | llc -march=x86 | grep memcpy | count 2
 
-%A = global [1000 x int] zeroinitializer
-%B = global [1000 x int] zeroinitializer
+ at A = global [32 x i32] zeroinitializer
+ at B = global [32 x i32] zeroinitializer
 
+declare void @llvm.memcpy.i32(i8*, i8*, i32, i32)
 
-void %main() {
+define void @main() {
   ; dword copy
-  call void %llvm.memcpy.i32(sbyte* cast (int* getelementptr ([1000 x int]* %A, long 0, long 0) to sbyte*),
-                           sbyte* cast (int* getelementptr ([1000 x int]* %B, long 0, long 0) to sbyte*),
-                           uint 4000, uint 4)
+  call void @llvm.memcpy.i32(i8* bitcast ([32 x i32]* @A to i8*),
+                           i8* bitcast ([32 x i32]* @B to i8*),
+                           i32 128, i32 4 )
 
   ; word copy
-  call void %llvm.memcpy.i32(sbyte* cast (int* getelementptr ([1000 x int]* %A, long 0, long 0) to sbyte*),
-                           sbyte* cast (int* getelementptr ([1000 x int]* %B, long 0, long 0) to sbyte*),
-                           uint 4000, uint 2)
+  call void @llvm.memcpy.i32( i8* bitcast ([32 x i32]* @A to i8*),
+                           i8* bitcast ([32 x i32]* @B to i8*),
+                           i32 128, i32 2 )
 
   ; byte copy
-  call void %llvm.memcpy.i32(sbyte* cast (int* getelementptr ([1000 x int]* %A, long 0, long 0) to sbyte*),
-                           sbyte* cast (int* getelementptr ([1000 x int]* %B, long 0, long 0) to sbyte*),
-                           uint 4000, uint 1)
+  call void @llvm.memcpy.i32( i8* bitcast ([32 x i32]* @A to i8*),
+                           i8* bitcast ([32 x i32]* @B to i8*),
+                            i32 128, i32 1 )
+
   ret void
 }