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llvm-project/llvm/test/CodeGen/X86/MachineBranchProb.ll

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PGO branch weight: update edge weights in SelectionDAGBuilder. When converting from "or + br" to two branches, or converting from "and + br" to two branches, we correctly update the edge weights of the two branches. The previous attempt at r200431 was reverted at r200434 because of two testing case failures. I modified my patch a little, but forgot to re-run "make check-all". Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of the patch's impact on branch probability which causes changes in spill placement. llvm-svn: 200502
2014-01-31 08:42:44 +08:00
; RUN: llc < %s -mtriple=x86_64-apple-darwin -print-machineinstrs=expand-isel-pseudos -o /dev/null 2>&1 | FileCheck %s
;; Make sure a transformation in SelectionDAGBuilder that converts "or + br" to
;; two branches correctly updates the branch probability.
@max_regno = common global i32 0, align 4
define void @test(i32* %old, i32 %final) {
for.cond:
br label %for.cond2
for.cond2: ; preds = %for.inc, %for.cond
%i.1 = phi i32 [ %inc19, %for.inc ], [ 0, %for.cond ]
%bit.0 = phi i32 [ %shl, %for.inc ], [ 1, %for.cond ]
%tobool = icmp eq i32 %bit.0, 0
[opaque pointer type] Add textual IR support for explicit type parameter to load instruction Essentially the same as the GEP change in r230786. A similar migration script can be used to update test cases, though a few more test case improvements/changes were required this time around: (r229269-r229278) import fileinput import sys import re pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)") for line in sys.stdin: sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line)) Reviewers: rafael, dexonsmith, grosser Differential Revision: http://reviews.llvm.org/D7649 llvm-svn: 230794
2015-02-28 05:17:42 +08:00
%v3 = load i32, i32* @max_regno, align 4
PGO branch weight: update edge weights in SelectionDAGBuilder. When converting from "or + br" to two branches, or converting from "and + br" to two branches, we correctly update the edge weights of the two branches. The previous attempt at r200431 was reverted at r200434 because of two testing case failures. I modified my patch a little, but forgot to re-run "make check-all". Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of the patch's impact on branch probability which causes changes in spill placement. llvm-svn: 200502
2014-01-31 08:42:44 +08:00
%cmp4 = icmp eq i32 %i.1, %v3
%or.cond = or i1 %tobool, %cmp4
br i1 %or.cond, label %for.inc20, label %for.inc, !prof !0
; CHECK: BB#1: derived from LLVM BB %for.cond2
Fix information loss in branch probability computation. Summary: This addresses PR 22718. When branch weights are too large, they were being clamped to the range [1, MaxWeightForBB]. But this clamping is only applied to edges that go outside the range, so it distorts the relative branch probabilities. This patch changes the weight calculation to scale every branch so the relative probabilities are preserved. The scaling is done differently now. First, all the branch weights are added up, and if the sum exceeds 32 bits, it computes an integer scale to bring all the weights within the range. The patch fixes an existing test that had slightly wrong branch probabilities due to the previous clamping. It now gets branch weights scaled accordingly. Reviewers: dexonsmith Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D9442 llvm-svn: 236750
2015-05-08 01:22:06 +08:00
; CHECK: Successors according to CFG: BB#3(56008718) BB#4(3615818718)
PGO branch weight: update edge weights in SelectionDAGBuilder. When converting from "or + br" to two branches, or converting from "and + br" to two branches, we correctly update the edge weights of the two branches. The previous attempt at r200431 was reverted at r200434 because of two testing case failures. I modified my patch a little, but forgot to re-run "make check-all". Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of the patch's impact on branch probability which causes changes in spill placement. llvm-svn: 200502
2014-01-31 08:42:44 +08:00
; CHECK: BB#4: derived from LLVM BB %for.cond2
Fix information loss in branch probability computation. Summary: This addresses PR 22718. When branch weights are too large, they were being clamped to the range [1, MaxWeightForBB]. But this clamping is only applied to edges that go outside the range, so it distorts the relative branch probabilities. This patch changes the weight calculation to scale every branch so the relative probabilities are preserved. The scaling is done differently now. First, all the branch weights are added up, and if the sum exceeds 32 bits, it computes an integer scale to bring all the weights within the range. The patch fixes an existing test that had slightly wrong branch probabilities due to the previous clamping. It now gets branch weights scaled accordingly. Reviewers: dexonsmith Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D9442 llvm-svn: 236750
2015-05-08 01:22:06 +08:00
; CHECK: Successors according to CFG: BB#3(56008718) BB#2(3559810000)
PGO branch weight: update edge weights in SelectionDAGBuilder. When converting from "or + br" to two branches, or converting from "and + br" to two branches, we correctly update the edge weights of the two branches. The previous attempt at r200431 was reverted at r200434 because of two testing case failures. I modified my patch a little, but forgot to re-run "make check-all". Testing case CodeGen/ARM/lsr-unfolded-offset.ll is updated because of the patch's impact on branch probability which causes changes in spill placement. llvm-svn: 200502
2014-01-31 08:42:44 +08:00
for.inc: ; preds = %for.cond2
%shl = shl i32 %bit.0, 1
%inc19 = add nsw i32 %i.1, 1
br label %for.cond2
for.inc20: ; preds = %for.cond2
ret void
}
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
2014-12-16 03:07:53 +08:00
!0 = !{!"branch_weights", i32 112017436, i32 -735157296}