[llvm] r261828 - Optimized loading (zextload) of i1 value from memory.

Elena Demikhovsky via llvm-commits llvm-commits at lists.llvm.org
Wed Feb 24 23:05:13 PST 2016


Author: delena
Date: Thu Feb 25 01:05:12 2016
New Revision: 261828

URL: http://llvm.org/viewvc/llvm-project?rev=261828&view=rev
Log:
Optimized loading (zextload) of i1 value from memory.
This patch is a partial revert of https://llvm.org/svn/llvm-project/llvm/trunk@237793.
Extra "and" causes performance degradation.

We assume that i1 is stored in zero-extended form. And store operation is responsible for zeroing upper bits.

Differential Revision: http://reviews.llvm.org/D17541


Modified:
    llvm/trunk/lib/Target/X86/X86InstrAVX512.td
    llvm/trunk/lib/Target/X86/X86InstrCompiler.td
    llvm/trunk/test/CodeGen/X86/and-encoding.ll
    llvm/trunk/test/CodeGen/X86/avx512-insert-extract.ll
    llvm/trunk/test/CodeGen/X86/avx512-mask-op.ll
    llvm/trunk/test/CodeGen/X86/masked_gather_scatter.ll
    llvm/trunk/test/CodeGen/X86/x86-shrink-wrapping.ll

Modified: llvm/trunk/lib/Target/X86/X86InstrAVX512.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrAVX512.td?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrAVX512.td (original)
+++ llvm/trunk/lib/Target/X86/X86InstrAVX512.td Thu Feb 25 01:05:12 2016
@@ -2193,14 +2193,6 @@ def : Pat<(store (i1 -1), addr:$dst), (M
 def : Pat<(store (i1  1), addr:$dst), (MOV8mi addr:$dst, (i8 1))>;
 def : Pat<(store (i1  0), addr:$dst), (MOV8mi addr:$dst, (i8 0))>;
 
-def truncstorei1 : PatFrag<(ops node:$val, node:$ptr),
-                           (truncstore node:$val, node:$ptr), [{
-  return cast<StoreSDNode>(N)->getMemoryVT() == MVT::i1;
-}]>;
-
-def : Pat<(truncstorei1 GR8:$src, addr:$dst),
-          (MOV8mr addr:$dst, GR8:$src)>;
-
 // With AVX-512 only, 8-bit mask is promoted to 16-bit mask.
 let Predicates = [HasAVX512, NoDQI] in {
   // GR from/to 8-bit mask without native support

Modified: llvm/trunk/lib/Target/X86/X86InstrCompiler.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrCompiler.td?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrCompiler.td (original)
+++ llvm/trunk/lib/Target/X86/X86InstrCompiler.td Thu Feb 25 01:05:12 2016
@@ -1139,12 +1139,13 @@ defm : CMOVmr<X86_COND_O , CMOVNO16rm, C
 defm : CMOVmr<X86_COND_NO, CMOVO16rm , CMOVO32rm , CMOVO64rm>;
 
 // zextload bool -> zextload byte
-def : Pat<(zextloadi8i1  addr:$src), (AND8ri (MOV8rm addr:$src), (i8 1))>;
-def : Pat<(zextloadi16i1 addr:$src), (AND16ri8 (MOVZX16rm8 addr:$src), (i16 1))>;
-def : Pat<(zextloadi32i1 addr:$src), (AND32ri8 (MOVZX32rm8 addr:$src), (i32 1))>;
+// i1 stored in one byte in zero-extended form.
+// Upper bits cleanup should be executed before Store.
+def : Pat<(zextloadi8i1  addr:$src), (MOV8rm addr:$src)>;
+def : Pat<(zextloadi16i1 addr:$src), (MOVZX16rm8 addr:$src)>;
+def : Pat<(zextloadi32i1 addr:$src), (MOVZX32rm8 addr:$src)>;
 def : Pat<(zextloadi64i1 addr:$src),
-          (SUBREG_TO_REG (i64 0),
-           (AND32ri8 (MOVZX32rm8 addr:$src), (i32 1)), sub_32bit)>;
+          (SUBREG_TO_REG (i64 0), (MOVZX32rm8 addr:$src), sub_32bit)>;
 
 // extload bool -> extload byte
 // When extloading from 16-bit and smaller memory locations into 64-bit

Modified: llvm/trunk/test/CodeGen/X86/and-encoding.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/and-encoding.ll?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/and-encoding.ll (original)
+++ llvm/trunk/test/CodeGen/X86/and-encoding.ll Thu Feb 25 01:05:12 2016
@@ -15,27 +15,18 @@ define void @f1() {
   ret void
 }
 
-define void @f2(i1 *%x, i16 *%y) {
+define void @f2(i16 %x, i1 *%y) {
 ; CHECK-LABEL: f2:
-; CHECK: andl	$1, %eax                # encoding: [0x83,0xe0,0x01]
-  %a = load i1, i1* %x
-  %b = zext i1 %a to i16
-  store i16 %b, i16* %y
+; CHECK: andl	$1, %edi                # encoding: [0x83,0xe7,0x01]
+  %c = trunc i16 %x to i1
+  store i1 %c, i1* %y
   ret void
 }
 
-define i32 @f3(i1 *%x) {
+define void @f3(i32 %x, i1 *%y) {
 ; CHECK-LABEL: f3:
-; CHECK: andl	$1, %eax                # encoding: [0x83,0xe0,0x01]
-  %a = load i1, i1* %x
-  %b = zext i1 %a to i32
-  ret i32 %b
-}
-
-define i64 @f4(i1 *%x) {
-; CHECK-LABEL: f4:
-; CHECK: andl	$1, %eax                # encoding: [0x83,0xe0,0x01]
-  %a = load i1, i1* %x
-  %b = zext i1 %a to i64
-  ret i64 %b
+; CHECK: andl	$1, %edi                # encoding: [0x83,0xe7,0x01]
+  %c = trunc i32 %x to i1
+  store i1 %c, i1* %y
+  ret void
 }

Modified: llvm/trunk/test/CodeGen/X86/avx512-insert-extract.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx512-insert-extract.ll?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx512-insert-extract.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx512-insert-extract.ll Thu Feb 25 01:05:12 2016
@@ -190,7 +190,6 @@ define i64 @test14(<8 x i64>%a, <8 x i64
 
 ;CHECK-LABEL: test15
 ;CHECK: movb (%rdi), %al
-;CHECK: andb $1, %al
 ;CHECK: movw    $-1, %ax
 ;CHECK: cmovew
 define i16 @test15(i1 *%addr) {
@@ -202,7 +201,6 @@ define i16 @test15(i1 *%addr) {
 
 ;CHECK-LABEL: test16
 ;CHECK: movb (%rdi), %al
-;CHECK: andw $1, %ax
 ;CHECK: kmovw
 ;CHECK: kshiftlw        $10
 ;CHECK: korw

Modified: llvm/trunk/test/CodeGen/X86/avx512-mask-op.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx512-mask-op.ll?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx512-mask-op.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx512-mask-op.ll Thu Feb 25 01:05:12 2016
@@ -1586,7 +1586,6 @@ define void @f1(i32 %c) {
 ; KNL-LABEL: f1:
 ; KNL:       ## BB#0: ## %entry
 ; KNL-NEXT:    movzbl {{.*}}(%rip), %edi
-; KNL-NEXT:    andl $1, %edi
 ; KNL-NEXT:    movl %edi, %eax
 ; KNL-NEXT:    andl $1, %eax
 ; KNL-NEXT:    kmovw %eax, %k0
@@ -1601,7 +1600,6 @@ define void @f1(i32 %c) {
 ; SKX-LABEL: f1:
 ; SKX:       ## BB#0: ## %entry
 ; SKX-NEXT:    movzbl {{.*}}(%rip), %edi
-; SKX-NEXT:    andl $1, %edi
 ; SKX-NEXT:    movl %edi, %eax
 ; SKX-NEXT:    andl $1, %eax
 ; SKX-NEXT:    kmovw %eax, %k0
@@ -1622,3 +1620,24 @@ entry:
 
 declare void @f2(i32) #1
 
+define void @store_i16_i1(i16 %x, i1 *%y) {
+; CHECK-LABEL: store_i16_i1:
+; CHECK:       ## BB#0:
+; CHECK-NEXT:    andl $1, %edi
+; CHECK-NEXT:    movb %dil, (%rsi)
+; CHECK-NEXT:    retq
+  %c = trunc i16 %x to i1
+  store i1 %c, i1* %y
+  ret void
+}
+
+define void @store_i8_i1(i8 %x, i1 *%y) {
+; CHECK-LABEL: store_i8_i1:
+; CHECK:       ## BB#0:
+; CHECK-NEXT:    andl $1, %edi
+; CHECK-NEXT:    movb %dil, (%rsi)
+; CHECK-NEXT:    retq
+  %c = trunc i8 %x to i1
+  store i1 %c, i1* %y
+  ret void
+}

Modified: llvm/trunk/test/CodeGen/X86/masked_gather_scatter.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/masked_gather_scatter.ll?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/masked_gather_scatter.ll (original)
+++ llvm/trunk/test/CodeGen/X86/masked_gather_scatter.ll Thu Feb 25 01:05:12 2016
@@ -1466,7 +1466,7 @@ define <3 x i32> @test30(<3 x i32*> %bas
 ; SKX-NEXT:    vpaddq %ymm1, %ymm0, %ymm1
 ; SKX-NEXT:    movb -{{[0-9]+}}(%rsp), %al
 ; SKX-NEXT:    # implicit-def: %XMM0
-; SKX-NEXT:    andb $1, %al
+; SKX-NEXT:    testb %al, %al
 ; SKX-NEXT:    je .LBB29_2
 ; SKX-NEXT:  # BB#1: # %cond.load
 ; SKX-NEXT:    vmovq %xmm1, %rax
@@ -1474,7 +1474,7 @@ define <3 x i32> @test30(<3 x i32*> %bas
 ; SKX-NEXT:  .LBB29_2: # %else
 ; SKX-NEXT:    kmovb %k1, -{{[0-9]+}}(%rsp)
 ; SKX-NEXT:    movb -{{[0-9]+}}(%rsp), %al
-; SKX-NEXT:    andb $1, %al
+; SKX-NEXT:    testb %al, %al
 ; SKX-NEXT:    je .LBB29_4
 ; SKX-NEXT:  # BB#3: # %cond.load1
 ; SKX-NEXT:    vpextrq $1, %xmm1, %rax
@@ -1482,7 +1482,7 @@ define <3 x i32> @test30(<3 x i32*> %bas
 ; SKX-NEXT:  .LBB29_4: # %else2
 ; SKX-NEXT:    kmovb %k1, -{{[0-9]+}}(%rsp)
 ; SKX-NEXT:    movb -{{[0-9]+}}(%rsp), %al
-; SKX-NEXT:    andb $1, %al
+; SKX-NEXT:    testb %al, %al
 ; SKX-NEXT:    je .LBB29_6
 ; SKX-NEXT:  # BB#5: # %cond.load4
 ; SKX-NEXT:    vextracti128 $1, %ymm1, %xmm1
@@ -1505,7 +1505,7 @@ define <3 x i32> @test30(<3 x i32*> %bas
 ; SKX_32-NEXT:    vpaddd %xmm1, %xmm0, %xmm2
 ; SKX_32-NEXT:    movb {{[0-9]+}}(%esp), %al
 ; SKX_32-NEXT:    # implicit-def: %XMM1
-; SKX_32-NEXT:    andb $1, %al
+; SKX_32-NEXT:    testb %al, %al
 ; SKX_32-NEXT:    je .LBB29_2
 ; SKX_32-NEXT:  # BB#1: # %cond.load
 ; SKX_32-NEXT:    vmovd %xmm2, %eax
@@ -1513,7 +1513,7 @@ define <3 x i32> @test30(<3 x i32*> %bas
 ; SKX_32-NEXT:  .LBB29_2: # %else
 ; SKX_32-NEXT:    kmovb %k1, {{[0-9]+}}(%esp)
 ; SKX_32-NEXT:    movb {{[0-9]+}}(%esp), %al
-; SKX_32-NEXT:    andb $1, %al
+; SKX_32-NEXT:    testb %al, %al
 ; SKX_32-NEXT:    je .LBB29_4
 ; SKX_32-NEXT:  # BB#3: # %cond.load1
 ; SKX_32-NEXT:    vpextrd $1, %xmm2, %eax
@@ -1522,7 +1522,7 @@ define <3 x i32> @test30(<3 x i32*> %bas
 ; SKX_32-NEXT:    vmovdqa32 {{[0-9]+}}(%esp), %xmm0
 ; SKX_32-NEXT:    kmovb %k1, (%esp)
 ; SKX_32-NEXT:    movb (%esp), %al
-; SKX_32-NEXT:    andb $1, %al
+; SKX_32-NEXT:    testb %al, %al
 ; SKX_32-NEXT:    je .LBB29_6
 ; SKX_32-NEXT:  # BB#5: # %cond.load4
 ; SKX_32-NEXT:    vpextrd $2, %xmm2, %eax

Modified: llvm/trunk/test/CodeGen/X86/x86-shrink-wrapping.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/x86-shrink-wrapping.ll?rev=261828&r1=261827&r2=261828&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/x86-shrink-wrapping.ll (original)
+++ llvm/trunk/test/CodeGen/X86/x86-shrink-wrapping.ll Thu Feb 25 01:05:12 2016
@@ -811,8 +811,6 @@ end:
 ;
 ; Load the value of b.
 ; CHECK: movb _b(%rip), [[BOOL:%cl]]
-; Extract i1 from the loaded value.
-; CHECK-NEXT: andb $1, [[BOOL]]
 ; Create the zero value for the select assignment.
 ; CHECK-NEXT: xorl [[CMOVE_VAL:%eax]], [[CMOVE_VAL]]
 ; CHECK-NEXT: testb [[BOOL]], [[BOOL]]




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