a6b2de3b59
This pass 'forwards' operand trees into statements that use them in order to avoid scalar dependencies. This minimal implementation handles only the case of speculatable instructions. We will successively add support for: - Hoisted loads - Read-only values - Synthesizable values - Loads - PHIs - Forwarding only parts of the tree Differential Revision: https://reviews.llvm.org/D35754 llvm-svn: 308825
43 lines
719 B
LLVM
43 lines
719 B
LLVM
; RUN: opt %loadPolly -polly-optree -analyze < %s | FileCheck %s -match-full-lines
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;
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; Do not move PHI nodes.
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;
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; for (int j = 0; j < n; j += 1) {
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; bodyA:
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; double val = 42.0;
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;
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; bodyB:
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; A[0] = val;
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; }
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;
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define void @func(i32 %n, double* noalias nonnull %A) {
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entry:
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br label %for
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for:
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%j = phi i32 [0, %entry], [%j.inc, %inc]
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%j.cmp = icmp slt i32 %j, %n
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br i1 %j.cmp, label %bodyA, label %exit
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bodyA:
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%val = phi double [42.0, %for]
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br label %bodyB
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bodyB:
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store double %val, double* %A
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br label %inc
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inc:
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%j.inc = add nuw nsw i32 %j, 1
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br label %for
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exit:
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br label %return
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return:
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ret void
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}
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; CHECK: ForwardOpTree executed, but did not modify anything
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