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tests: Drop -polly-detect-unprofitable and -polly-no-early-exit These flags are now always passed to all tests and need to be disabled if not needed. Disabling these flags, rather than passing them to almost all tests, significantly simplfies our RUN: lines. llvm-svn: 249422
2015-10-06 23:36:44 +08:00
; RUN: opt %loadPolly -polly-scops -analyze < %s | FileCheck %s
[FIX] Do not assume only one loop can be left at a time llvm-svn: 247291
2015-09-10 23:53:59 +08:00
;
[ScopDetect] Reject loop with multiple exit blocks. The current statement domain derivation algorithm does not (always) consider that different exit blocks of a loop can have different conditions to be reached. From the code for (int i = n; ; i-=2) { if (i <= 0) goto even; if (i <= 1) goto odd; A[i] = i; } even: A[0] = 42; return; odd: A[1] = 21; return; Polly currently derives the following domains: Stmt_even_critedge Domain := [n] -> { Stmt_even_critedge[] }; Stmt_odd Domain := [n] -> { Stmt_odd[] : (1 + n) mod 2 = 0 and n > 0 }; while the domain for the odd case is correct, Stmt_even is assumed to be executed unconditionally, which is obviously wrong. While projecting out the loop dimension in `adjustDomainDimensions`, it does not consider that there are other exit condition that have matched before. I don't know a how to fix this without changing a lot of code. Therefore This patch rejects loops with multiple exist blocks to fix the miscompile of test-suite's uuencode. The odd condition is transformed by LLVM to %cmp1 = icmp eq i64 %indvars.iv, 1 such that the project_out in adjustDomainDimensions() indeed only matches for odd n (using this condition only, we'd have an infinite loop otherwise). The even condition manifests as %cmp = icmp slt i64 %indvars.iv, 3 Because buildDomainsWithBranchConstraints() does not consider other exit conditions, it has to assume that the induction variable will eventually be lower than 3 and taking this exit. IMHO we need to reuse the algorithm that determines the number of iterations (addLoopBoundsToHeaderDomain) to determine which exit condition applies first. It has to happen in buildDomainsWithBranchConstraints() because the result will need to propagate to successor BBs. Currently addLoopBoundsToHeaderDomain() just look for union of all backedge conditions (which means leaving not the loop here). The patch in llvm.org/PR35465 changes it to look for exit conditions instead. This is required because there might be other exit conditions that do not alternatively go back to the loop header. Differential Revision: https://reviews.llvm.org/D45649 llvm-svn: 330858
2018-04-26 02:53:33 +08:00
; The SCoP contains a loop with multiple exit blocks (BBs after leaving
; the loop). The current implementation of deriving their domain derives
; only a common domain for all of the exit blocks. We disabled loops with
; multiple exit blocks until this is fixed.
; XFAIL: *
;
[FIX] Do not assume only one loop can be left at a time llvm-svn: 247291
2015-09-10 23:53:59 +08:00
; void foo(long n, float A[100]) {
; for (long j = 0; j < n; j++) {
; for (long i = j; i < n; i++) {
; if (i < 0)
; goto end;
;
; if (i >= 100)
; goto end;
;
; A[i] += i;
; }
; }
; end:
; return;
; }
;
; CHECK: Domain :=
Update to ISL 0.16.1 llvm-svn: 257898
2016-01-15 23:54:45 +08:00
; CHECK: [n] -> { Stmt_if_end_7[i0, i1] : i0 >= 0 and 0 <= i1 <= 99 - i0 and i1 < n - i0 };
[FIX] Do not assume only one loop can be left at a time llvm-svn: 247291
2015-09-10 23:53:59 +08:00
;
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
define void @foo(i64 %n, float* %A) {
entry:
br label %for.cond
for.cond: ; preds = %for.inc.8, %entry
%j.0 = phi i64 [ 0, %entry ], [ %inc9, %for.inc.8 ]
%cmp = icmp slt i64 %j.0, %n
br i1 %cmp, label %for.body, label %for.end.10
for.body: ; preds = %for.cond
br label %for.cond.1
for.cond.1: ; preds = %for.inc, %for.body
%i.0 = phi i64 [ %j.0, %for.body ], [ %inc, %for.inc ]
%cmp2 = icmp slt i64 %i.0, %n
br i1 %cmp2, label %for.body.3, label %for.end
for.body.3: ; preds = %for.cond.1
br i1 false, label %if.then, label %if.end
if.then: ; preds = %for.body.3
br label %end
if.end: ; preds = %for.body.3
%cmp5 = icmp sgt i64 %i.0, 99
br i1 %cmp5, label %if.then.6, label %if.end.7
if.then.6: ; preds = %if.end
br label %end
if.end.7: ; preds = %if.end
%conv = sitofp i64 %i.0 to float
%arrayidx = getelementptr inbounds float, float* %A, i64 %i.0
%tmp = load float, float* %arrayidx, align 4
%add = fadd float %tmp, %conv
store float %add, float* %arrayidx, align 4
br label %for.inc
for.inc: ; preds = %if.end.7
%inc = add nuw nsw i64 %i.0, 1
br label %for.cond.1
for.end: ; preds = %for.cond.1
br label %for.inc.8
for.inc.8: ; preds = %for.end
%inc9 = add nuw nsw i64 %j.0, 1
br label %for.cond
for.end.10: ; preds = %for.cond
br label %end
end: ; preds = %for.end.10, %if.then.6, %if.then
ret void
}