[llvm] r235261 - [MemCpyOpt] Don't force i64 when promoting memset/memcpy sizes.

[Ahmed Bougacha]

Author: ab
Date: Sat Apr 18 18:06:04 2015
New Revision: 235261

URL: http://llvm.org/viewvc/llvm-project?rev=235261&view=rev
Log:
[MemCpyOpt] Don't force i64 when promoting memset/memcpy sizes.

Harden r235258 to support any integer bitwidth.  The quick glance at
the reference made me think only i32 and i64 were valid types, but
they're not special, so any overload is legal.

Thanks to David Majnemer for noticing!

Modified:
    llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp
    llvm/trunk/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll

Modified: llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp?rev=235261&r1=235260&r2=235261&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/MemCpyOptimizer.cpp Sat Apr 18 18:06:04 2015
@@ -876,10 +876,13 @@ bool MemCpyOpt::processMemSetMemCpyDepen
 
   IRBuilder<> Builder(MemCpy->getNextNode());
 
-  // If the sizes have different types (i32 vs i64), promote both to i64.
+  // If the sizes have different types, zext the smaller one.
   if (DestSize->getType() != SrcSize->getType()) {
-    DestSize = Builder.CreateZExt(DestSize, Builder.getInt64Ty());
-    SrcSize = Builder.CreateZExt(SrcSize, Builder.getInt64Ty());
+    if (DestSize->getType()->getIntegerBitWidth() >
+        SrcSize->getType()->getIntegerBitWidth())
+      SrcSize = Builder.CreateZExt(SrcSize, DestSize->getType());
+    else
+      DestSize = Builder.CreateZExt(DestSize, SrcSize->getType());
   }
 
   Value *MemsetLen =

Modified: llvm/trunk/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll?rev=235261&r1=235260&r2=235261&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll (original)
+++ llvm/trunk/test/Transforms/MemCpyOpt/memset-memcpy-redundant-memset.ll Sat Apr 18 18:06:04 2015
@@ -31,6 +31,36 @@ define void @test_different_types_i32_i6
   ret void
 }
 
+; CHECK-LABEL: define void @test_different_types_i128_i32
+; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %src_size, i32 1, i1 false)
+; CHECK-DAG: [[SRCSIZE:%[0-9]+]] = zext i32 %src_size to i128
+; CHECK-DAG: [[DST:%[0-9]+]] = getelementptr i8, i8* %dst, i128 [[SRCSIZE]]
+; CHECK-DAG: [[ULE:%[0-9]+]] = icmp ule i128 %dst_size, [[SRCSIZE]]
+; CHECK-DAG: [[SIZEDIFF:%[0-9]+]] = sub i128 %dst_size, [[SRCSIZE]]
+; CHECK-DAG: [[SIZE:%[0-9]+]] = select i1 [[ULE]], i128 0, i128 [[SIZEDIFF]]
+; CHECK-NEXT: call void @llvm.memset.p0i8.i128(i8* [[DST]], i8 %c, i128 [[SIZE]], i32 1, i1 false)
+; CHECK-NEXT: ret void
+define void @test_different_types_i128_i32(i8* %dst, i8* %src, i128 %dst_size, i32 %src_size, i8 %c) {
+  call void @llvm.memset.p0i8.i128(i8* %dst, i8 %c, i128 %dst_size, i32 1, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %src_size, i32 1, i1 false)
+  ret void
+}
+
+; CHECK-LABEL: define void @test_different_types_i32_i128
+; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i128(i8* %dst, i8* %src, i128 %src_size, i32 1, i1 false)
+; CHECK-DAG: [[DSTSIZE:%[0-9]+]] = zext i32 %dst_size to i128
+; CHECK-DAG: [[DST:%[0-9]+]] = getelementptr i8, i8* %dst, i128 %src_size
+; CHECK-DAG: [[ULE:%[0-9]+]] = icmp ule i128 [[DSTSIZE]], %src_size
+; CHECK-DAG: [[SIZEDIFF:%[0-9]+]] = sub i128 [[DSTSIZE]], %src_size
+; CHECK-DAG: [[SIZE:%[0-9]+]] = select i1 [[ULE]], i128 0, i128 [[SIZEDIFF]]
+; CHECK-NEXT: call void @llvm.memset.p0i8.i128(i8* [[DST]], i8 %c, i128 [[SIZE]], i32 1, i1 false)
+; CHECK-NEXT: ret void
+define void @test_different_types_i32_i128(i8* %dst, i8* %src, i32 %dst_size, i128 %src_size, i8 %c) {
+  call void @llvm.memset.p0i8.i32(i8* %dst, i8 %c, i32 %dst_size, i32 1, i1 false)
+  call void @llvm.memcpy.p0i8.p0i8.i128(i8* %dst, i8* %src, i128 %src_size, i32 1, i1 false)
+  ret void
+}
+
 ; CHECK-LABEL: define void @test_different_types_i64_i32
 ; CHECK-NEXT: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %src, i32 %src_size, i32 1, i1 false)
 ; CHECK-DAG: [[SRCSIZE:%[0-9]+]] = zext i32 %src_size to i64
@@ -84,3 +114,5 @@ declare void @llvm.memset.p0i8.i64(i8* n
 declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1)
 declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1)
 declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1)
+declare void @llvm.memset.p0i8.i128(i8* nocapture, i8, i128, i32, i1)
+declare void @llvm.memcpy.p0i8.p0i8.i128(i8* nocapture, i8* nocapture readonly, i128, i32, i1)