llvm-project/llvm/test/CodeGen/ARM/ifcvt-branch-weight-bug.ll

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; RUN: llc < %s -mtriple=armv4t--linux-androideabi -stop-after=if-converter | FileCheck %s
; Fix a bug triggered in IfConverterTriangle when CvtBB has multiple
; predecessors.
; PR18752
%classK = type { i8, %classF }
%classF = type { i8 }
%classL = type { %classG, i32, i32 }
%classG = type { %classL* }
%classM2 = type { %classL }
define zeroext i1 @test(%classK* %this, %classL* nocapture readnone %p0, %classM2* nocapture readnone %p1, %classM2* nocapture readnone %p2, i32 %a0) align 2 {
entry:
br i1 undef, label %for.end, label %for.body
; Before if conversion, we have
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; for.body -> lor.lhs.false.i (50%)
; -> for.cond.backedge (50%)
; lor.lhs.false.i -> for.cond.backedge (100%)
; -> cond.false.i (0%)
; Afer if conversion, we have
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; for.body -> for.cond.backedge (100%)
; -> cond.false.i (0%)
; CHECK: bb.1.for.body:
[BPI] Improve static heuristics for "cold" paths. Current approach doesn't work well in cases when multiple paths are predicted to be "cold". By "cold" paths I mean those containing "unreachable" instruction, call marked with 'cold' attribute and 'unwind' handler of 'invoke' instruction. The issue is that heuristics are applied one by one until the first match and essentially ignores relative hotness/coldness of other paths. New approach unifies processing of "cold" paths by assigning predefined absolute weight to each block estimated to be "cold". Then we propagate these weights up/down IR similarly to existing approach. And finally set up edge probabilities based on estimated block weights. One important difference is how we propagate weight up. Existing approach propagates the same weight to all blocks that are post-dominated by a block with some "known" weight. This is useless at least because it always gives 50\50 distribution which is assumed by default anyway. Worse, it causes the algorithm to skip further heuristics and can miss setting more accurate probability. New algorithm propagates the weight up only to the blocks that dominates and post-dominated by a block with some "known" weight. In other words, those blocks that are either always executed or not executed together. In addition new approach processes loops in an uniform way as well. Essentially loop exit edges are estimated as "cold" paths relative to back edges and should be considered uniformly with other coldness/hotness markers. Reviewed By: yrouban Differential Revision: https://reviews.llvm.org/D79485
2020-06-18 17:20:55 +08:00
; CHECK: successors: %bb.2(0x80000000), %bb.4(0x00000000)
for.body:
br i1 undef, label %for.cond.backedge, label %lor.lhs.false.i, !prof !1
for.cond.backedge:
%tobool = icmp eq %classL* %p0, null
br i1 %tobool, label %for.end, label %for.body
lor.lhs.false.i:
%tobool.i.i7 = icmp eq i32 %a0, 0
br i1 %tobool.i.i7, label %for.cond.backedge, label %cond.false.i
cond.false.i:
call void @_Z3fn1v()
unreachable
for.end:
%tobool.i.i9 = icmp eq i32 %a0, 32
br i1 %tobool.i.i9, label %if.else.i.i, label %if.then.i.i
if.then.i.i:
store %classL* null, %classL** undef, align 4
br label %_ZN1M6spliceEv.exit
if.else.i.i:
store %classL* null, %classL** null, align 4
br label %_ZN1M6spliceEv.exit
_ZN1M6spliceEv.exit:
[opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction One of several parallel first steps to remove the target type of pointers, replacing them with a single opaque pointer type. This adds an explicit type parameter to the gep instruction so that when the first parameter becomes an opaque pointer type, the type to gep through is still available to the instructions. * This doesn't modify gep operators, only instructions (operators will be handled separately) * Textual IR changes only. Bitcode (including upgrade) and changing the in-memory representation will be in separate changes. * geps of vectors are transformed as: getelementptr <4 x float*> %x, ... ->getelementptr float, <4 x float*> %x, ... Then, once the opaque pointer type is introduced, this will ultimately look like: getelementptr float, <4 x ptr> %x with the unambiguous interpretation that it is a vector of pointers to float. * address spaces remain on the pointer, not the type: getelementptr float addrspace(1)* %x ->getelementptr float, float addrspace(1)* %x Then, eventually: getelementptr float, ptr addrspace(1) %x Importantly, the massive amount of test case churn has been automated by same crappy python code. I had to manually update a few test cases that wouldn't fit the script's model (r228970,r229196,r229197,r229198). The python script just massages stdin and writes the result to stdout, I then wrapped that in a shell script to handle replacing files, then using the usual find+xargs to migrate all the files. update.py: import fileinput import sys import re ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))") normrep = re.compile( r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))") def conv(match, line): if not match: return line line = match.groups()[0] if len(match.groups()[5]) == 0: line += match.groups()[2] line += match.groups()[3] line += ", " line += match.groups()[1] line += "\n" return line for line in sys.stdin: if line.find("getelementptr ") == line.find("getelementptr inbounds"): if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("): line = conv(re.match(ibrep, line), line) elif line.find("getelementptr ") != line.find("getelementptr ("): line = conv(re.match(normrep, line), line) sys.stdout.write(line) apply.sh: for name in "$@" do python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name" rm -f "$name.tmp" done The actual commands: From llvm/src: find test/ -name *.ll | xargs ./apply.sh From llvm/src/tools/clang: find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}" From llvm/src/tools/polly: find test/ -name *.ll | xargs ./apply.sh After that, check-all (with llvm, clang, clang-tools-extra, lld, compiler-rt, and polly all checked out). The extra 'rm' in the apply.sh script is due to a few files in clang's test suite using interesting unicode stuff that my python script was throwing exceptions on. None of those files needed to be migrated, so it seemed sufficient to ignore those cases. Reviewers: rafael, dexonsmith, grosser Differential Revision: http://reviews.llvm.org/D7636 llvm-svn: 230786
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%LIS = getelementptr inbounds %classK, %classK* %this, i32 0, i32 1
call void @_ZN1F10handleMoveEb(%classF* %LIS, i1 zeroext false)
unreachable
}
declare %classL* @_ZN1M1JI1LS1_EcvPS1_Ev(%classM2*)
declare void @_ZN1F10handleMoveEb(%classF*, i1 zeroext)
declare void @_Z3fn1v()
IR: Make metadata typeless in assembly Now that `Metadata` is typeless, reflect that in the assembly. These are the matching assembly changes for the metadata/value split in r223802. - Only use the `metadata` type when referencing metadata from a call intrinsic -- i.e., only when it's used as a `Value`. - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode` when referencing it from call intrinsics. So, assembly like this: define @foo(i32 %v) { call void @llvm.foo(metadata !{i32 %v}, metadata !0) call void @llvm.foo(metadata !{i32 7}, metadata !0) call void @llvm.foo(metadata !1, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{metadata !3}, metadata !0) ret void, !bar !2 } !0 = metadata !{metadata !2} !1 = metadata !{i32* @global} !2 = metadata !{metadata !3} !3 = metadata !{} turns into this: define @foo(i32 %v) { call void @llvm.foo(metadata i32 %v, metadata !0) call void @llvm.foo(metadata i32 7, metadata !0) call void @llvm.foo(metadata i32* @global, metadata !0) call void @llvm.foo(metadata !3, metadata !0) call void @llvm.foo(metadata !{!3}, metadata !0) ret void, !bar !2 } !0 = !{!2} !1 = !{i32* @global} !2 = !{!3} !3 = !{} I wrote an upgrade script that handled almost all of the tests in llvm and many of the tests in cfe (even handling many `CHECK` lines). I've attached it (or will attach it in a moment if you're speedy) to PR21532 to help everyone update their out-of-tree testcases. This is part of PR21532. llvm-svn: 224257
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!0 = !{!"clang version 3.5"}
!1 = !{!"branch_weights", i32 62, i32 62}