[llvm] r220047 - [PowerPC] Enable use of lxvw4x/stxvw4x in VSX code generation

Bill Schmidt wschmidt at linux.vnet.ibm.com
Fri Oct 17 08:13:39 PDT 2014


Author: wschmidt
Date: Fri Oct 17 10:13:38 2014
New Revision: 220047

URL: http://llvm.org/viewvc/llvm-project?rev=220047&view=rev
Log:
[PowerPC] Enable use of lxvw4x/stxvw4x in VSX code generation

Currently the VSX support enables use of lxvd2x and stxvd2x for 2x64
types, but does not yet use lxvw4x and stxvw4x for 4x32 types.  This
patch adds that support.

As with lxvd2x/stxvd2x, this involves straightforward overriding of
the patterns normally recognized for lvx/stvx, with preference given
to the VSX patterns when VSX is enabled.

In addition, the logic for permitting misaligned memory accesses is
modified so that v4r32 and v4i32 are treated the same as v2f64 and
v2i64 when VSX is enabled.  Finally, the DAG generation for unaligned
loads is changed to just use a normal LOAD (which will become lxvw4x)
on P8 and later hardware, where unaligned loads are preferred over
lvsl/lvx/lvx/vperm.

A number of tests now generate the VSX loads/stores instead of
lvx/stvx, so this patch adds VSX variants to those tests.  I've also
added <4 x float> tests to the vsx.ll test case, and created a
vsx-p8.ll test case to be used for testing code generation for the
P8Vector feature.  For now, that simply tests the unaligned load/store
behavior.

This has been tested along with a temporary patch to enable the VSX
and P8Vector features, with no new regressions encountered with or
without the temporary patch applied.

Added:
    llvm/trunk/test/CodeGen/PowerPC/vsx-p8.ll
Modified:
    llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp
    llvm/trunk/lib/Target/PowerPC/PPCInstrVSX.td
    llvm/trunk/test/CodeGen/PowerPC/unal4-std.ll
    llvm/trunk/test/CodeGen/PowerPC/unaligned.ll
    llvm/trunk/test/CodeGen/PowerPC/vec-abi-align.ll
    llvm/trunk/test/CodeGen/PowerPC/vec_misaligned.ll
    llvm/trunk/test/CodeGen/PowerPC/vrspill.ll
    llvm/trunk/test/CodeGen/PowerPC/vsx.ll

Modified: llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp Fri Oct 17 10:13:38 2014
@@ -8312,6 +8312,8 @@ SDValue PPCTargetLowering::PerformDAGCom
     unsigned ABIAlignment = getDataLayout()->getABITypeAlignment(Ty);
     if (ISD::isNON_EXTLoad(N) && VT.isVector() &&
         TM.getSubtarget<PPCSubtarget>().hasAltivec() &&
+        // P8 and later hardware should just use LOAD.
+        !TM.getSubtarget<PPCSubtarget>().hasP8Vector() &&
         (VT == MVT::v16i8 || VT == MVT::v8i16 ||
          VT == MVT::v4i32 || VT == MVT::v4f32) &&
         LD->getAlignment() < ABIAlignment) {
@@ -9204,7 +9206,8 @@ bool PPCTargetLowering::allowsMisaligned
 
   if (VT.getSimpleVT().isVector()) {
     if (Subtarget.hasVSX()) {
-      if (VT != MVT::v2f64 && VT != MVT::v2i64)
+      if (VT != MVT::v2f64 && VT != MVT::v2i64 &&
+          VT != MVT::v4f32 && VT != MVT::v4i32)
         return false;
     } else {
       return false;

Modified: llvm/trunk/lib/Target/PowerPC/PPCInstrVSX.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCInstrVSX.td?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCInstrVSX.td (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCInstrVSX.td Fri Oct 17 10:13:38 2014
@@ -63,7 +63,8 @@ let Uses = [RM] in {
 
     def LXVW4X : XX1Form<31, 780,
                          (outs vsrc:$XT), (ins memrr:$src),
-                         "lxvw4x $XT, $src", IIC_LdStLFD, []>;
+                         "lxvw4x $XT, $src", IIC_LdStLFD,
+                         [(set v4i32:$XT, (load xoaddr:$src))]>;
   }
 
   // Store indexed instructions
@@ -80,7 +81,8 @@ let Uses = [RM] in {
 
     def STXVW4X : XX1Form<31, 908,
                          (outs), (ins vsrc:$XT, memrr:$dst),
-                         "stxvw4x $XT, $dst", IIC_LdStSTFD, []>;
+                         "stxvw4x $XT, $dst", IIC_LdStSTFD,
+                         [(store v4i32:$XT, xoaddr:$dst)]>;
   }
 
   // Add/Mul Instructions
@@ -811,6 +813,13 @@ def : Pat<(sext_inreg v2i64:$C, v2i32),
 def : Pat<(v2f64 (sint_to_fp (sext_inreg v2i64:$C, v2i32))),
           (XVCVSXWDP (XXSLDWI $C, $C, 1))>;
 
+// Loads.
+def : Pat<(v4i32 (load xoaddr:$src)), (LXVW4X xoaddr:$src)>;
+
+// Stores.
+def : Pat<(store v4i32:$rS, xoaddr:$dst),
+          (STXVW4X $rS, xoaddr:$dst)>;
+
 } // AddedComplexity
 } // HasVSX
 

Modified: llvm/trunk/test/CodeGen/PowerPC/unal4-std.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/unal4-std.ll?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/unal4-std.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/unal4-std.ll Fri Oct 17 10:13:38 2014
@@ -1,4 +1,5 @@
-; RUN: llc < %s -mcpu=pwr7 | FileCheck %s
+; RUN: llc < %s -mcpu=pwr7 -mattr=-vsx| FileCheck %s
+; RUN: llc < %s -mcpu=pwr7 -mattr=+vsx | FileCheck -check-prefix=CHECK-VSX %s
 target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64"
 target triple = "powerpc64-unknown-linux-gnu"
 
@@ -22,6 +23,9 @@ if.end210:
 ; a multiple of 4).
 ; CHECK: @copy_to_conceal
 ; CHECK: stdx {{[0-9]+}}, 0,
+
+; CHECK-VSX: @copy_to_conceal
+; CHECK-VSX: stxvw4x {{[0-9]+}}, 0,
 }
 
 attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" }

Modified: llvm/trunk/test/CodeGen/PowerPC/unaligned.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/unaligned.ll?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/unaligned.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/unaligned.ll Fri Oct 17 10:13:38 2014
@@ -92,10 +92,14 @@ entry:
 ; CHECK-DAG: stdx
 ; CHECK: stdx
 
+; For VSX on P7, unaligned loads and stores are preferable to aligned
+; stack slots, but lvsl/vperm is better still.  (On P8 lxvw4x is preferable.)
+; Using unaligned stxvw4x is preferable on both machines.
 ; CHECK-VSX: @foo6
-; CHECK-VSX-DAG: ld
-; CHECK-VSX-DAG: ld
-; CHECK-VSX-DAG: stdx
-; CHECK-VSX: stdx
+; CHECK-VSX-DAG: lvsl
+; CHECK-VSX-DAG: lvx
+; CHECK-VSX-DAG: lvx
+; CHECK-VSX: vperm
+; CHECK-VSX: stxvw4x
 }
 

Modified: llvm/trunk/test/CodeGen/PowerPC/vec-abi-align.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/vec-abi-align.ll?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/vec-abi-align.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/vec-abi-align.ll Fri Oct 17 10:13:38 2014
@@ -1,4 +1,5 @@
-; RUN: llc -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 < %s | FileCheck %s
+; RUN: llc -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 -mattr=-vsx < %s | FileCheck %s
+; RUN: llc -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr7 -mattr=+vsx < %s | FileCheck -check-prefix=CHECK-VSX %s
 target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64"
 target triple = "powerpc64-unknown-linux-gnu"
 
@@ -16,6 +17,10 @@ entry:
 ; CHECK-LABEL: @test1
 ; CHECK: stvx 2,
 ; CHECK: blr
+
+; CHECK-VSX-LABEL: @test1
+; CHECK-VSX: stxvw4x 34,
+; CHECK-VSX: blr
 }
 
 ; Function Attrs: nounwind
@@ -35,6 +40,13 @@ entry:
 ; CHECK: addi [[REGB:[0-9]+]], 1, 112
 ; CHECK: lvx 2, [[REGB]], [[REG16]]
 ; CHECK: blr
+
+; CHECK-VSX-LABEL: @test2
+; CHECK-VSX: ld {{[0-9]+}}, 112(1)
+; CHECK-VSX: li [[REG16:[0-9]+]], 16
+; CHECK-VSX: addi [[REGB:[0-9]+]], 1, 112
+; CHECK-VSX: lxvw4x {{[0-9]+}}, [[REGB]], [[REG16]]
+; CHECK-VSX: blr
 }
 
 ; Function Attrs: nounwind
@@ -54,6 +66,13 @@ entry:
 ; CHECK: addi [[REGB:[0-9]+]], 1, 128
 ; CHECK: lvx 2, [[REGB]], [[REG16]]
 ; CHECK: blr
+
+; CHECK-VSX-LABEL: @test3
+; CHECK-VSX: ld {{[0-9]+}}, 128(1)
+; CHECK-VSX: li [[REG16:[0-9]+]], 16
+; CHECK-VSX: addi [[REGB:[0-9]+]], 1, 128
+; CHECK-VSX: lxvw4x {{[0-9]+}}, [[REGB]], [[REG16]]
+; CHECK-VSX: blr
 }
 
 attributes #0 = { nounwind }

Modified: llvm/trunk/test/CodeGen/PowerPC/vec_misaligned.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/vec_misaligned.ll?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/vec_misaligned.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/vec_misaligned.ll Fri Oct 17 10:13:38 2014
@@ -1,5 +1,5 @@
 ; RUN: llc < %s -march=ppc32 -mcpu=g5 | FileCheck %s
-; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mattr=+altivec | FileCheck %s
+; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mattr=+altivec -mattr=-vsx -mattr=-power8-vector | FileCheck %s
 ; RUN: llc < %s -mtriple=powerpc64le-unknown-linux-gnu -mattr=+altivec | FileCheck %s -check-prefix=CHECK-LE
 
 target datalayout = "E-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f128:64:128"

Modified: llvm/trunk/test/CodeGen/PowerPC/vrspill.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/vrspill.ll?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/vrspill.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/vrspill.ll Fri Oct 17 10:13:38 2014
@@ -1,5 +1,7 @@
-; RUN: llc -O0 -mtriple=powerpc-unknown-linux-gnu -mattr=+altivec -verify-machineinstrs < %s | FileCheck %s
-; RUN: llc -O0 -mtriple=powerpc64-unknown-linux-gnu -mattr=+altivec -verify-machineinstrs -fast-isel=false < %s | FileCheck %s
+; RUN: llc -O0 -mtriple=powerpc-unknown-linux-gnu -mattr=+altivec -mattr=-vsx -verify-machineinstrs < %s | FileCheck %s
+; RUN: llc -O0 -mtriple=powerpc64-unknown-linux-gnu -mattr=+altivec -mattr=-vsx -verify-machineinstrs -fast-isel=false < %s | FileCheck %s
+; RUN: llc -O0 -mtriple=powerpc-unknown-linux-gnu -mattr=+altivec -mattr=+vsx -verify-machineinstrs < %s | FileCheck -check-prefix=CHECK-VSX %s
+; RUN: llc -O0 -mtriple=powerpc64-unknown-linux-gnu -mattr=+altivec -mattr=+vsx -verify-machineinstrs -fast-isel=false < %s | FileCheck -check-prefix=CHECK-VSX %s
 
 ; This verifies that we generate correct spill/reload code for vector regs.
 
@@ -15,4 +17,9 @@ entry:
 
 ; CHECK: stvx 2,
 
+; We would prefer to test for "stxvw4x 34," but current -O0 code
+; needlessly generates "vor 3,2,2 / stxvw4x 35,0,3", so we'll settle for
+; the opcode.
+; CHECK-VSX: stxvw4x
+
 declare void @foo(i32*)

Added: llvm/trunk/test/CodeGen/PowerPC/vsx-p8.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/vsx-p8.ll?rev=220047&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/vsx-p8.ll (added)
+++ llvm/trunk/test/CodeGen/PowerPC/vsx-p8.ll Fri Oct 17 10:13:38 2014
@@ -0,0 +1,42 @@
+; RUN: llc -mcpu=pwr8 -mattr=+power8-vector < %s | FileCheck %s
+target datalayout = "E-m:e-i64:64-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+; Unaligned loads/stores on P8 and later should use VSX where possible.
+
+define <2 x double> @test28u(<2 x double>* %a) {
+  %v = load <2 x double>* %a, align 8
+  ret <2 x double> %v
+
+; CHECK-LABEL: @test28u
+; CHECK: lxvd2x 34, 0, 3
+; CHECK: blr
+}
+
+define void @test29u(<2 x double>* %a, <2 x double> %b) {
+  store <2 x double> %b, <2 x double>* %a, align 8
+  ret void
+
+; CHECK-LABEL: @test29u
+; CHECK: stxvd2x 34, 0, 3
+; CHECK: blr
+}
+
+define <4 x float> @test32u(<4 x float>* %a) {
+  %v = load <4 x float>* %a, align 8
+  ret <4 x float> %v
+
+; CHECK-LABEL: @test32u
+; CHECK: lxvw4x 34, 0, 3
+; CHECK: blr
+}
+
+define void @test33u(<4 x float>* %a, <4 x float> %b) {
+  store <4 x float> %b, <4 x float>* %a, align 8
+  ret void
+
+; CHECK-LABEL: @test33u
+; CHECK: stxvw4x 34, 0, 3
+; CHECK: blr
+}
+

Modified: llvm/trunk/test/CodeGen/PowerPC/vsx.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/vsx.ll?rev=220047&r1=220046&r2=220047&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/vsx.ll (original)
+++ llvm/trunk/test/CodeGen/PowerPC/vsx.ll Fri Oct 17 10:13:38 2014
@@ -356,6 +356,63 @@ define void @test31(<2 x i64>* %a, <2 x
 ; CHECK: blr
 }
 
+define <4 x float> @test32(<4 x float>* %a) {
+  %v = load <4 x float>* %a, align 16
+  ret <4 x float> %v
+
+; CHECK-LABEL: @test32
+; CHECK: lxvw4x 34, 0, 3
+; CHECK: blr
+}
+
+define void @test33(<4 x float>* %a, <4 x float> %b) {
+  store <4 x float> %b, <4 x float>* %a, align 16
+  ret void
+
+; CHECK-LABEL: @test33
+; CHECK: stxvw4x 34, 0, 3
+; CHECK: blr
+}
+
+define <4 x float> @test32u(<4 x float>* %a) {
+  %v = load <4 x float>* %a, align 8
+  ret <4 x float> %v
+
+; CHECK-LABEL: @test32u
+; CHECK-DAG: lvsl
+; CHECK-DAG: lvx
+; CHECK-DAG: lvx
+; CHECK: vperm 2,
+; CHECK: blr
+}
+
+define void @test33u(<4 x float>* %a, <4 x float> %b) {
+  store <4 x float> %b, <4 x float>* %a, align 8
+  ret void
+
+; CHECK-LABEL: @test33u
+; CHECK: stxvw4x 34, 0, 3
+; CHECK: blr
+}
+
+define <4 x i32> @test34(<4 x i32>* %a) {
+  %v = load <4 x i32>* %a, align 16
+  ret <4 x i32> %v
+
+; CHECK-LABEL: @test34
+; CHECK: lxvw4x 34, 0, 3
+; CHECK: blr
+}
+
+define void @test35(<4 x i32>* %a, <4 x i32> %b) {
+  store <4 x i32> %b, <4 x i32>* %a, align 16
+  ret void
+
+; CHECK-LABEL: @test35
+; CHECK: stxvw4x 34, 0, 3
+; CHECK: blr
+}
+
 define <2 x double> @test40(<2 x i64> %a) {
   %v = uitofp <2 x i64> %a to <2 x double>
   ret <2 x double> %v





More information about the llvm-commits mailing list