[llvm] r372275 - [WebAssembly] Restore defaults for stores per memop
Thomas Lively via llvm-commits
llvm-commits at lists.llvm.org
Wed Sep 18 16:18:16 PDT 2019
Author: tlively
Date: Wed Sep 18 16:18:16 2019
New Revision: 372275
URL: http://llvm.org/viewvc/llvm-project?rev=372275&view=rev
Log:
[WebAssembly] Restore defaults for stores per memop
Summary:
Large slowdowns were observed in Rust due to many small, constant
sized copies in conjunction with poorly-optimized memory.copy
implementations. Since memory.copy cannot be expected to be inlined
efficiently by engines at this time, stop using it for the smallest
copies. We continue to lower all memcpy intrinsics to memory.copy,
though.
Reviewers: aheejin, alexcrichton
Subscribers: dschuff, sbc100, jgravelle-google, hiraditya, JDevlieghere, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67639
Modified:
llvm/trunk/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
llvm/trunk/test/CodeGen/WebAssembly/bulk-memory.ll
Modified: llvm/trunk/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp?rev=372275&r1=372274&r2=372275&view=diff
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp Wed Sep 18 16:18:16 2019
@@ -259,16 +259,6 @@ WebAssemblyTargetLowering::WebAssemblyTa
setMaxAtomicSizeInBitsSupported(64);
- if (Subtarget->hasBulkMemory()) {
- // Use memory.copy and friends over multiple loads and stores
- MaxStoresPerMemcpy = 1;
- MaxStoresPerMemcpyOptSize = 1;
- MaxStoresPerMemmove = 1;
- MaxStoresPerMemmoveOptSize = 1;
- MaxStoresPerMemset = 1;
- MaxStoresPerMemsetOptSize = 1;
- }
-
// Override the __gnu_f2h_ieee/__gnu_h2f_ieee names so that the f32 name is
// consistent with the f64 and f128 names.
setLibcallName(RTLIB::FPEXT_F16_F32, "__extendhfsf2");
Modified: llvm/trunk/test/CodeGen/WebAssembly/bulk-memory.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/WebAssembly/bulk-memory.ll?rev=372275&r1=372274&r2=372275&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/WebAssembly/bulk-memory.ll (original)
+++ llvm/trunk/test/CodeGen/WebAssembly/bulk-memory.ll Wed Sep 18 16:18:16 2019
@@ -142,8 +142,8 @@ define void @memset_1024(i8* %dest, i8 %
}
; The following tests check that frame index elimination works for
-; bulk memory instructions. The stack pointer is bumped by 16 instead
-; of 10 because the stack pointer in WebAssembly is currently always
+; bulk memory instructions. The stack pointer is bumped by 112 instead
+; of 100 because the stack pointer in WebAssembly is currently always
; 16-byte aligned, even in leaf functions, although it is not written
; back to the global in this case.
@@ -156,17 +156,17 @@ define void @memset_1024(i8* %dest, i8 %
; NO-BULK-MEM-NOT: memory.copy
; BULK-MEM-NEXT: .functype memcpy_alloca_src (i32) -> ()
; BULK-MEM-NEXT: global.get $push[[L0:[0-9]+]]=, __stack_pointer
-; BULK-MEM-NEXT: i32.const $push[[L1:[0-9]+]]=, 16
+; BULK-MEM-NEXT: i32.const $push[[L1:[0-9]+]]=, 112
; BULK-MEM-NEXT: i32.sub $push[[L2:[0-9]+]]=, $pop[[L0]], $pop[[L1]]
-; BULK-MEM-NEXT: i32.const $push[[L3:[0-9]+]]=, 6
+; BULK-MEM-NEXT: i32.const $push[[L3:[0-9]+]]=, 12
; BULK-MEM-NEXT: i32.add $push[[L4:[0-9]+]]=, $pop[[L2]], $pop[[L3]]
-; BULK-MEM-NEXT: i32.const $push[[L5:[0-9]+]]=, 10
+; BULK-MEM-NEXT: i32.const $push[[L5:[0-9]+]]=, 100
; BULK-MEM-NEXT: memory.copy 0, 0, $0, $pop[[L4]], $pop[[L5]]
; BULK-MEM-NEXT: return
define void @memcpy_alloca_src(i8* %dst) {
- %a = alloca [10 x i8]
- %p = bitcast [10 x i8]* %a to i8*
- call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %p, i32 10, i1 false)
+ %a = alloca [100 x i8]
+ %p = bitcast [100 x i8]* %a to i8*
+ call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dst, i8* %p, i32 100, i1 false)
ret void
}
@@ -174,17 +174,17 @@ define void @memcpy_alloca_src(i8* %dst)
; NO-BULK-MEM-NOT: memory.copy
; BULK-MEM-NEXT: .functype memcpy_alloca_dst (i32) -> ()
; BULK-MEM-NEXT: global.get $push[[L0:[0-9]+]]=, __stack_pointer
-; BULK-MEM-NEXT: i32.const $push[[L1:[0-9]+]]=, 16
+; BULK-MEM-NEXT: i32.const $push[[L1:[0-9]+]]=, 112
; BULK-MEM-NEXT: i32.sub $push[[L2:[0-9]+]]=, $pop[[L0]], $pop[[L1]]
-; BULK-MEM-NEXT: i32.const $push[[L3:[0-9]+]]=, 6
+; BULK-MEM-NEXT: i32.const $push[[L3:[0-9]+]]=, 12
; BULK-MEM-NEXT: i32.add $push[[L4:[0-9]+]]=, $pop[[L2]], $pop[[L3]]
-; BULK-MEM-NEXT: i32.const $push[[L5:[0-9]+]]=, 10
+; BULK-MEM-NEXT: i32.const $push[[L5:[0-9]+]]=, 100
; BULK-MEM-NEXT: memory.copy 0, 0, $pop[[L4]], $0, $pop[[L5]]
; BULK-MEM-NEXT: return
define void @memcpy_alloca_dst(i8* %src) {
- %a = alloca [10 x i8]
- %p = bitcast [10 x i8]* %a to i8*
- call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %src, i32 10, i1 false)
+ %a = alloca [100 x i8]
+ %p = bitcast [100 x i8]* %a to i8*
+ call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %src, i32 100, i1 false)
ret void
}
@@ -192,16 +192,16 @@ define void @memcpy_alloca_dst(i8* %src)
; NO-BULK-MEM-NOT: memory.fill
; BULK-MEM-NEXT: .functype memset_alloca (i32) -> ()
; BULK-MEM-NEXT: global.get $push[[L0:[0-9]+]]=, __stack_pointer
-; BULK-MEM-NEXT: i32.const $push[[L1:[0-9]+]]=, 16
+; BULK-MEM-NEXT: i32.const $push[[L1:[0-9]+]]=, 112
; BULK-MEM-NEXT: i32.sub $push[[L2:[0-9]+]]=, $pop[[L0]], $pop[[L1]]
-; BULK-MEM-NEXT: i32.const $push[[L3:[0-9]+]]=, 6
+; BULK-MEM-NEXT: i32.const $push[[L3:[0-9]+]]=, 12
; BULK-MEM-NEXT: i32.add $push[[L4:[0-9]+]]=, $pop[[L2]], $pop[[L3]]
-; BULK-MEM-NEXT: i32.const $push[[L5:[0-9]+]]=, 10
+; BULK-MEM-NEXT: i32.const $push[[L5:[0-9]+]]=, 100
; BULK-MEM-NEXT: memory.fill 0, $pop[[L4]], $0, $pop[[L5]]
; BULK-MEM-NEXT: return
define void @memset_alloca(i8 %val) {
- %a = alloca [10 x i8]
- %p = bitcast [10 x i8]* %a to i8*
- call void @llvm.memset.p0i8.i32(i8* %p, i8 %val, i32 10, i1 false)
+ %a = alloca [100 x i8]
+ %p = bitcast [100 x i8]* %a to i8*
+ call void @llvm.memset.p0i8.i32(i8* %p, i8 %val, i32 100, i1 false)
ret void
}
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