llvm-project/llvm/test/CodeGen/PowerPC/vsx-ldst.ll

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[PowerPC] Add vec_vsx_ld and vec_vsx_st intrinsics This patch enables the vec_vsx_ld and vec_vsx_st intrinsics for PowerPC, which provide programmer access to the lxvd2x, lxvw4x, stxvd2x, and stxvw4x instructions. New LLVM intrinsics are provided to represent these four instructions in IntrinsicsPowerPC.td. These are patterned after the similar intrinsics for lvx and stvx (Altivec). In PPCInstrVSX.td, these intrinsics are tied to the code gen patterns, with additional patterns to allow plain vanilla loads and stores to still generate these instructions. At -O1 and higher the intrinsics are immediately converted to loads and stores in InstCombineCalls.cpp. This will open up more optimization opportunities while still allowing the correct instructions to be generated. (Similar code exists for aligned Altivec loads and stores.) The new intrinsics are added to the code that checks for consecutive loads and stores in PPCISelLowering.cpp, as well as to PPCTargetLowering::getTgtMemIntrinsic(). There's a new test to verify the correct instructions are generated. The loads and stores tend to be reordered, so the test just counts their number. It runs at -O2, as it's not very effective to test this at -O0, when many unnecessary loads and stores are generated. I ended up having to modify vsx-fma-m.ll. It turns out this test case is slightly unreliable, but I don't know a good way to prevent problems with it. The xvmaddmdp instructions read and write the same register, which is one of the multiplicands. Commutativity allows either to be chosen. If the FMAs are reordered differently than expected by the test, the register assignment can be different as a result. Hopefully this doesn't change often. There is a companion patch for Clang. llvm-svn: 221767
2014-11-12 12:19:40 +08:00
; RUN: llc -mcpu=pwr8 -mattr=+vsx -O2 -mtriple=powerpc64-unknown-linux-gnu < %s > %t
; RUN: grep lxvw4x < %t | count 3
; RUN: grep lxvd2x < %t | count 3
; RUN: grep stxvw4x < %t | count 3
; RUN: grep stxvd2x < %t | count 3
; RUN: llc -mcpu=pwr8 -mattr=+vsx -O0 -fast-isel=1 -mtriple=powerpc64-unknown-linux-gnu < %s > %t
; RUN: grep lxvw4x < %t | count 3
; RUN: grep lxvd2x < %t | count 3
; RUN: grep stxvw4x < %t | count 3
; RUN: grep stxvd2x < %t | count 3
[PowerPC] Add vec_vsx_ld and vec_vsx_st intrinsics This patch enables the vec_vsx_ld and vec_vsx_st intrinsics for PowerPC, which provide programmer access to the lxvd2x, lxvw4x, stxvd2x, and stxvw4x instructions. New LLVM intrinsics are provided to represent these four instructions in IntrinsicsPowerPC.td. These are patterned after the similar intrinsics for lvx and stvx (Altivec). In PPCInstrVSX.td, these intrinsics are tied to the code gen patterns, with additional patterns to allow plain vanilla loads and stores to still generate these instructions. At -O1 and higher the intrinsics are immediately converted to loads and stores in InstCombineCalls.cpp. This will open up more optimization opportunities while still allowing the correct instructions to be generated. (Similar code exists for aligned Altivec loads and stores.) The new intrinsics are added to the code that checks for consecutive loads and stores in PPCISelLowering.cpp, as well as to PPCTargetLowering::getTgtMemIntrinsic(). There's a new test to verify the correct instructions are generated. The loads and stores tend to be reordered, so the test just counts their number. It runs at -O2, as it's not very effective to test this at -O0, when many unnecessary loads and stores are generated. I ended up having to modify vsx-fma-m.ll. It turns out this test case is slightly unreliable, but I don't know a good way to prevent problems with it. The xvmaddmdp instructions read and write the same register, which is one of the multiplicands. Commutativity allows either to be chosen. If the FMAs are reordered differently than expected by the test, the register assignment can be different as a result. Hopefully this doesn't change often. There is a companion patch for Clang. llvm-svn: 221767
2014-11-12 12:19:40 +08:00
[PowerPC 1/4] Little-endian adjustments for VSX loads/stores This patch addresses the inherent big-endian bias in the lxvd2x, lxvw4x, stxvd2x, and stxvw4x instructions. These instructions load vector elements into registers left-to-right (with the first element loaded into the high-order bits of the register), regardless of the endian setting of the processor. However, these are the only vector memory instructions that permit unaligned storage accesses, so we want to use them for little-endian. To make this work, a lxvd2x or lxvw4x is replaced with an lxvd2x followed by an xxswapd, which swaps the doublewords. This works for lxvw4x as well as lxvd2x, because for lxvw4x on an LE system the vector elements are in LE order (right-to-left) within each doubleword. (Thus after lxvw2x of a <4 x float> the elements will appear as 1, 0, 3, 2. Following the swap, they will appear as 3, 2, 0, 1, as desired.) For stores, an stxvd2x or stxvw4x is replaced with an stxvd2x preceded by an xxswapd. Introduction of extra swap instructions provides correctness, but obviously is not ideal from a performance perspective. Future patches will address this with optimizations to remove most of the introduced swaps, which have proven effective in other implementations. The introduction of the swaps is performed during lowering of LOAD, STORE, INTRINSIC_W_CHAIN, and INTRINSIC_VOID operations. The latter are used to translate intrinsics that specify the VSX loads and stores directly into equivalent sequences for little endian. Thus code that uses vec_vsx_ld and vec_vsx_st does not have to be modified to be ported from BE to LE. We introduce new PPCISD opcodes for LXVD2X, STXVD2X, and XXSWAPD for use during this lowering step. In PPCInstrVSX.td, we add new SDType and SDNode definitions for these (PPClxvd2x, PPCstxvd2x, PPCxxswapd). These are recognized during instruction selection and mapped to the correct instructions. Several tests that were written to use -mcpu=pwr7 or pwr8 are modified to disable VSX on LE variants because code generation changes with this and subsequent patches in this set. I chose to include all of these in the first patch than try to rigorously sort out which tests were broken by one or another of the patches. Sorry about that. The new test vsx-ldst-builtin-le.ll, and the changes to vsx-ldst.ll, are disabled until LE support is enabled because of breakages that occur as noted in those tests. They are re-enabled in patch 4/4. llvm-svn: 223783
2014-12-10 00:35:51 +08:00
;; Note: The LE test variant is disabled until LE support for VSX is enabled,
;; as otherwise we fail to get the expected counts.
; R;UN: llc -mcpu=pwr8 -mattr=+vsx -O2 -mtriple=powerpc64le-unknown-linux-gnu < %s > %t
; R;UN: grep lxvd2x < %t | count 6
; R;UN: grep stxvd2x < %t | count 6
; R;UN: grep xxpermdi < %t | count 12
[PowerPC] Add vec_vsx_ld and vec_vsx_st intrinsics This patch enables the vec_vsx_ld and vec_vsx_st intrinsics for PowerPC, which provide programmer access to the lxvd2x, lxvw4x, stxvd2x, and stxvw4x instructions. New LLVM intrinsics are provided to represent these four instructions in IntrinsicsPowerPC.td. These are patterned after the similar intrinsics for lvx and stvx (Altivec). In PPCInstrVSX.td, these intrinsics are tied to the code gen patterns, with additional patterns to allow plain vanilla loads and stores to still generate these instructions. At -O1 and higher the intrinsics are immediately converted to loads and stores in InstCombineCalls.cpp. This will open up more optimization opportunities while still allowing the correct instructions to be generated. (Similar code exists for aligned Altivec loads and stores.) The new intrinsics are added to the code that checks for consecutive loads and stores in PPCISelLowering.cpp, as well as to PPCTargetLowering::getTgtMemIntrinsic(). There's a new test to verify the correct instructions are generated. The loads and stores tend to be reordered, so the test just counts their number. It runs at -O2, as it's not very effective to test this at -O0, when many unnecessary loads and stores are generated. I ended up having to modify vsx-fma-m.ll. It turns out this test case is slightly unreliable, but I don't know a good way to prevent problems with it. The xvmaddmdp instructions read and write the same register, which is one of the multiplicands. Commutativity allows either to be chosen. If the FMAs are reordered differently than expected by the test, the register assignment can be different as a result. Hopefully this doesn't change often. There is a companion patch for Clang. llvm-svn: 221767
2014-11-12 12:19:40 +08:00
@vsi = global <4 x i32> <i32 -1, i32 2, i32 -3, i32 4>, align 16
@vui = global <4 x i32> <i32 0, i32 1, i32 2, i32 3>, align 16
@vf = global <4 x float> <float -1.500000e+00, float 2.500000e+00, float -3.500000e+00, float 4.500000e+00>, align 16
@vsll = global <2 x i64> <i64 255, i64 -937>, align 16
@vull = global <2 x i64> <i64 1447, i64 2894>, align 16
@vd = global <2 x double> <double 3.500000e+00, double -7.500000e+00>, align 16
@res_vsi = common global <4 x i32> zeroinitializer, align 16
@res_vui = common global <4 x i32> zeroinitializer, align 16
@res_vf = common global <4 x float> zeroinitializer, align 16
@res_vsll = common global <2 x i64> zeroinitializer, align 16
@res_vull = common global <2 x i64> zeroinitializer, align 16
@res_vd = common global <2 x double> zeroinitializer, align 16
; Function Attrs: nounwind
define void @test1() {
entry:
%0 = load <4 x i32>* @vsi, align 16
%1 = load <4 x i32>* @vui, align 16
%2 = load <4 x i32>* bitcast (<4 x float>* @vf to <4 x i32>*), align 16
%3 = load <2 x double>* bitcast (<2 x i64>* @vsll to <2 x double>*), align 16
%4 = load <2 x double>* bitcast (<2 x i64>* @vull to <2 x double>*), align 16
%5 = load <2 x double>* @vd, align 16
store <4 x i32> %0, <4 x i32>* @res_vsi, align 16
store <4 x i32> %1, <4 x i32>* @res_vui, align 16
store <4 x i32> %2, <4 x i32>* bitcast (<4 x float>* @res_vf to <4 x i32>*), align 16
store <2 x double> %3, <2 x double>* bitcast (<2 x i64>* @res_vsll to <2 x double>*), align 16
store <2 x double> %4, <2 x double>* bitcast (<2 x i64>* @res_vull to <2 x double>*), align 16
store <2 x double> %5, <2 x double>* @res_vd, align 16
ret void
}