Some enhancements for memcpy / memset inline expansion.

1. Teach it to use overlapping unaligned load / store to copy / set the trailing
   bytes. e.g. On 86, use two pairs of movups / movaps for 17 - 31 byte copies.
2. Use f64 for memcpy / memset on targets where i64 is not legal but f64 is. e.g.
   x86 and ARM.
3. When memcpy from a constant string, do *not* replace the load with a constant
   if it's not possible to materialize an integer immediate with a single
   instruction (required a new target hook: TLI.isIntImmLegal()).
4. Use unaligned load / stores more aggressively if target hooks indicates they
   are "fast".
5. Update ARM target hooks to use unaligned load / stores. e.g. vld1.8 / vst1.8.
   Also increase the threshold to something reasonable (8 for memset, 4 pairs
   for memcpy).

This significantly improves Dhrystone, up to 50% on ARM iOS devices.

rdar://12760078


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169791 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 103 insertions, 6 deletions

diff --git a/test/CodeGen/ARM/memcpy-inline.ll b/test/CodeGen/ARM/memcpy-inline.ll
index dc772827f2..d846e5cb26 100644
--- a/test/CodeGen/ARM/memcpy-inline.ll
+++ b/test/CodeGen/ARM/memcpy-inline.ll
@@ -1,18 +1,115 @@
-; RUN: llc < %s -mtriple=thumbv7-apple-darwin -disable-post-ra | FileCheck %s
-
-; CHECK: ldrd
-; CHECK: strd
-; CHECK: ldrb
+; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a8 -pre-RA-sched=source -disable-post-ra | FileCheck %s
 
 %struct.x = type { i8, i8, i8, i8, i8, i8, i8, i8, i8, i8, i8 }
 
 @src = external global %struct.x
 @dst = external global %struct.x
 
-define i32 @t() {
+@.str1 = private unnamed_addr constant [31 x i8] c"DHRYSTONE PROGRAM, SOME STRING\00", align 1
+@.str2 = private unnamed_addr constant [36 x i8] c"DHRYSTONE PROGRAM, SOME STRING BLAH\00", align 1
+@.str3 = private unnamed_addr constant [24 x i8] c"DHRYSTONE PROGRAM, SOME\00", align 1
+@.str4 = private unnamed_addr constant [18 x i8] c"DHRYSTONE PROGR  \00", align 1
+@.str5 = private unnamed_addr constant [7 x i8] c"DHRYST\00", align 1
+@.str6 = private unnamed_addr constant [14 x i8] c"/tmp/rmXXXXXX\00", align 1
+@spool.splbuf = internal global [512 x i8] zeroinitializer, align 16
+
+define i32 @t0() {
 entry:
+; CHECK: t0:
+; CHECK: vldr [[REG1:d[0-9]+]],
+; CHECK: vstr [[REG1]], 
   call void @llvm.memcpy.p0i8.p0i8.i32(i8* getelementptr inbounds (%struct.x* @dst, i32 0, i32 0), i8* getelementptr inbounds (%struct.x* @src, i32 0, i32 0), i32 11, i32 8, i1 false)
   ret i32 0
 }
 
+define void @t1(i8* nocapture %C) nounwind {
+entry:
+; CHECK: t1:
+; CHECK: vld1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r1]
+; CHECK: vst1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r0]
+; CHECK: adds r0, #15
+; CHECK: adds r1, #15
+; CHECK: vld1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r1]
+; CHECK: vst1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r0]
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %C, i8* getelementptr inbounds ([31 x i8]* @.str1, i64 0, i64 0), i64 31, i32 1, i1 false)
+  ret void
+}
+
+define void @t2(i8* nocapture %C) nounwind {
+entry:
+; CHECK: t2:
+; CHECK: ldr [[REG2:r[0-9]+]], [r1, #32]
+; CHECK: str [[REG2]], [r0, #32]
+; CHECK: vld1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r1]
+; CHECK: vst1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r0]
+; CHECK: adds r0, #16
+; CHECK: adds r1, #16
+; CHECK: vld1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r1]
+; CHECK: vst1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r0]
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %C, i8* getelementptr inbounds ([36 x i8]* @.str2, i64 0, i64 0), i64 36, i32 1, i1 false)
+  ret void
+}
+
+define void @t3(i8* nocapture %C) nounwind {
+entry:
+; CHECK: t3:
+; CHECK: vld1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r1]
+; CHECK: vst1.8 {d{{[0-9]+}}, d{{[0-9]+}}}, [r0]
+; CHECK: adds r0, #16
+; CHECK: adds r1, #16
+; CHECK: vld1.8 {d{{[0-9]+}}}, [r1]
+; CHECK: vst1.8 {d{{[0-9]+}}}, [r0]
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %C, i8* getelementptr inbounds ([24 x i8]* @.str3, i64 0, i64 0), i64 24, i32 1, i1 false)
+  ret void
+}
+
+define void @t4(i8* nocapture %C) nounwind {
+entry:
+; CHECK: t4:
+; CHECK: vld1.8 {[[REG3:d[0-9]+]], [[REG4:d[0-9]+]]}, [r1]
+; CHECK: vst1.8 {[[REG3]], [[REG4]]}, [r0]
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %C, i8* getelementptr inbounds ([18 x i8]* @.str4, i64 0, i64 0), i64 18, i32 1, i1 false)
+  ret void
+}
+
+define void @t5(i8* nocapture %C) nounwind {
+entry:
+; CHECK: t5:
+; CHECK: movs [[REG5:r[0-9]+]], #0
+; CHECK: strb [[REG5]], [r0, #6]
+; CHECK: movw [[REG6:r[0-9]+]], #21587
+; CHECK: strh [[REG6]], [r0, #4]
+; CHECK: ldr [[REG7:r[0-9]+]], 
+; CHECK: str [[REG7]]
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %C, i8* getelementptr inbounds ([7 x i8]* @.str5, i64 0, i64 0), i64 7, i32 1, i1 false)
+  ret void
+}
+
+define void @t6() nounwind {
+entry:
+; CHECK: t6:
+; CHECK: vld1.8 {[[REG8:d[0-9]+]]}, [r0]
+; CHECK: vstr [[REG8]], [r1]
+; CHECK: adds r1, #6
+; CHECK: adds r0, #6
+; CHECK: vld1.8
+; CHECK: vst1.16
+  call void @llvm.memcpy.p0i8.p0i8.i64(i8* getelementptr inbounds ([512 x i8]* @spool.splbuf, i64 0, i64 0), i8* getelementptr inbounds ([14 x i8]* @.str6, i64 0, i64 0), i64 14, i32 1, i1 false)
+  ret void
+}
+
+%struct.Foo = type { i32, i32, i32, i32 }
+
+define void @t7(%struct.Foo* nocapture %a, %struct.Foo* nocapture %b) nounwind {
+entry:
+; CHECK: t7
+; CHECK: vld1.32
+; CHECK: vst1.32
+  %0 = bitcast %struct.Foo* %a to i8*
+  %1 = bitcast %struct.Foo* %b to i8*
+  tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %0, i8* %1, i32 16, i32 4, i1 false)
+  ret void
+}
+
 declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind