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[CGP] Fix Complex addressing mode for offset
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Authored by skatkov on Dec 14 2017, 12:51 AM.

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Reviewers

john.brawn
reames

Commits

rGdf84b50eed89: Merging r322056: --------------------------------------------------------------…
rG4d1dd6b53abd: [CGP] Fix Complex addressing mode for offset
rL322645: Merging r322056:
rL322056: [CGP] Fix Complex addressing mode for offset

Summary

If the offset is differ in two addressing mode we can continue only if
ScaleReg is not set due to we will use it as merge of different offsets.

Diff Detail

Repository: rL LLVM

Event Timeline

skatkov created this revision.Dec 14 2017, 12:51 AM

Ping, we need this fix to enable select handling in complex addressing mode.

LGTM

This revision is now accepted and ready to land.Jan 2 2018, 2:16 PM

Closed by commit rL322056: [CGP] Fix Complex addressing mode for offset (authored by skatkov). · Explain WhyJan 8 2018, 8:38 PM

This revision was automatically updated to reflect the committed changes.

Revision Contents

Path

Size

llvm/

trunk/

lib/

CodeGen/

CodeGenPrepare.cpp

7 lines

test/

Transforms/

CodeGenPrepare/

X86/

sink-addrmode-select.ll

19 lines

Diff 129030

llvm/trunk/lib/CodeGen/CodeGenPrepare.cpp

Show First 20 Lines • Show All 2,694 Lines • ▼ Show 20 Lines	else if (DifferentField != ThisDifferentField)
DifferentField = ExtAddrMode::MultipleFields;		DifferentField = ExtAddrMode::MultipleFields;

// If NewAddrMode differs in only one dimension, and that dimension isn't		// If NewAddrMode differs in only one dimension, and that dimension isn't
// the amount that ScaledReg is scaled by, then we can handle it by		// the amount that ScaledReg is scaled by, then we can handle it by
// inserting a phi/select later on. Even if NewAddMode is the same		// inserting a phi/select later on. Even if NewAddMode is the same
// we still need to collect it due to original value is different.		// we still need to collect it due to original value is different.
// And later we will need all original values as anchors during		// And later we will need all original values as anchors during
// finding the common Phi node.		// finding the common Phi node.
		// We also must reject the case when base offset is different and
		// scale reg is not null, we cannot handle this case due to merge of
		// different offsets will be used as ScaleReg.
if (DifferentField != ExtAddrMode::MultipleFields &&		if (DifferentField != ExtAddrMode::MultipleFields &&
DifferentField != ExtAddrMode::ScaleField) {		DifferentField != ExtAddrMode::ScaleField &&
		(DifferentField != ExtAddrMode::BaseOffsField \|\|
		!NewAddrMode.ScaledReg)) {
AddrModes.emplace_back(NewAddrMode);		AddrModes.emplace_back(NewAddrMode);
return true;		return true;
}		}

// We couldn't combine NewAddrMode with the rest, so return failure.		// We couldn't combine NewAddrMode with the rest, so return failure.
AddrModes.clear();		AddrModes.clear();
return false;		return false;
}		}
▲ Show 20 Lines • Show All 3,871 Lines • Show Last 20 Lines

llvm/trunk/test/Transforms/CodeGenPrepare/X86/sink-addrmode-select.ll

				; RUN: opt -S -codegenprepare -disable-complex-addr-modes=false -addr-sink-new-select=true %s \| FileCheck %s --check-prefix=CHECK
				target datalayout =
				"e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
				target triple = "x86_64-unknown-linux-gnu"

				; Select when both offset and scale reg are present.
				define i64 @test1(i1 %c, i64* %b, i64 %scale) {
				; CHECK-LABEL: @test1
				entry:
				; CHECK-LABEL: entry:
				%g = getelementptr inbounds i64, i64* %b, i64 %scale
				%g1 = getelementptr inbounds i64, i64* %g, i64 8
				%g2 = getelementptr inbounds i64, i64* %g, i64 16
				%s = select i1 %c, i64* %g1, i64* %g2
				; CHECK-NOT: sunkaddr
				%v = load i64 , i64* %s, align 8
				ret i64 %v
				}