[llvm] r223929 - Match new shuffle codegen for MOVHPD patterns

[Sanjay Patel]

Author: spatel
Date: Wed Dec 10 10:58:54 2014
New Revision: 223929

URL: http://llvm.org/viewvc/llvm-project?rev=223929&view=rev
Log:
Match new shuffle codegen for MOVHPD patterns

Add patterns to match SSE (shufpd) and AVX (vpermilpd) shuffle codegen
when storing the high element of a v2f64. The existing patterns were
only checking for an unpckh type of shuffle. 

http://llvm.org/bugs/show_bug.cgi?id=21791

Differential Revision: http://reviews.llvm.org/D6586


Modified:
    llvm/trunk/lib/Target/X86/X86InstrSSE.td
    llvm/trunk/test/CodeGen/X86/extractelement-load.ll

Modified: llvm/trunk/lib/Target/X86/X86InstrSSE.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrSSE.td?rev=223929&r1=223928&r2=223929&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrSSE.td (original)
+++ llvm/trunk/lib/Target/X86/X86InstrSSE.td Wed Dec 10 10:58:54 2014
@@ -1332,6 +1332,8 @@ let Predicates = [HasAVX] in {
                  (bc_v4i32 (v2i64 (X86vzload addr:$src2)))),
             (VMOVHPSrm VR128:$src1, addr:$src2)>;
 
+  // VMOVHPD patterns
+  
   // FIXME: Instead of X86Unpckl, there should be a X86Movlhpd here, the problem
   // is during lowering, where it's not possible to recognize the load fold
   // cause it has two uses through a bitcast. One use disappears at isel time
@@ -1344,6 +1346,11 @@ let Predicates = [HasAVX] in {
   def : Pat<(v2f64 (X86Unpckl VR128:$src1,
                       (bc_v2f64 (v2i64 (scalar_to_vector (loadi64 addr:$src2)))))),
             (VMOVHPDrm VR128:$src1, addr:$src2)>;
+
+  def : Pat<(store (f64 (vector_extract
+                          (v2f64 (X86VPermilpi VR128:$src, (i8 1))),
+                          (iPTR 0))), addr:$dst),
+            (VMOVHPDmr addr:$dst, VR128:$src)>;
 }
 
 let Predicates = [UseSSE1] in {
@@ -1357,6 +1364,8 @@ let Predicates = [UseSSE1] in {
 }
 
 let Predicates = [UseSSE2] in {
+  // MOVHPD patterns
+
   // FIXME: Instead of X86Unpckl, there should be a X86Movlhpd here, the problem
   // is during lowering, where it's not possible to recognize the load fold
   // cause it has two uses through a bitcast. One use disappears at isel time
@@ -1369,6 +1378,11 @@ let Predicates = [UseSSE2] in {
   def : Pat<(v2f64 (X86Unpckl VR128:$src1,
                       (bc_v2f64 (v2i64 (scalar_to_vector (loadi64 addr:$src2)))))),
             (MOVHPDrm VR128:$src1, addr:$src2)>;
+
+  def : Pat<(store (f64 (vector_extract
+                          (v2f64 (X86Shufp VR128:$src, VR128:$src, (i8 1))),
+                          (iPTR 0))), addr:$dst),
+            (MOVHPDmr addr:$dst, VR128:$src)>;
 }
 
 //===----------------------------------------------------------------------===//

Modified: llvm/trunk/test/CodeGen/X86/extractelement-load.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/extractelement-load.ll?rev=223929&r1=223928&r2=223929&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/extractelement-load.ll (original)
+++ llvm/trunk/test/CodeGen/X86/extractelement-load.ll Wed Dec 10 10:58:54 2014
@@ -1,5 +1,6 @@
 ; RUN: llc < %s -march=x86 -mattr=+sse2 -mcpu=yonah | FileCheck %s
 ; RUN: llc < %s -march=x86-64 -mattr=+sse2 -mcpu=core2 | FileCheck %s
+; RUN: llc < %s -march=x86-64 -mattr=+avx -mcpu=btver2 | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
@@ -29,16 +30,15 @@ undef, i32 7, i32 9, i32 undef, i32 13,
 ; This case could easily end up inf-looping in the DAG combiner due to an
 ; low alignment load of the vector which prevents us from reliably forming a
 ; narrow load.
-; FIXME: It would be nice to detect whether the target has fast and legal
-; unaligned loads and use them here.
+
+; The expected codegen is identical for the AVX case except
+; load/store instructions will have a leading 'v', so we don't
+; need to special-case the checks.
+
 define void @t3() {
 ; CHECK-LABEL: t3:
-;
-; This movs the entire vector, shuffling the high double down. If we fixed the
-; FIXME above it would just move the high double directly.
 ; CHECK: movupd
-; CHECK: shufpd
-; CHECK: movlpd
+; CHECK: movhpd
 
 bb:
   %tmp13 = load <2 x double>* undef, align 1