mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-19 19:12:56 +02:00
Generalize the cast-of-addrec folding to handle folding of SCEVs like
(sext i8 {-128,+,1} to i64) to i64 {-128,+,1}, where the iteration
crosses from negative to positive, but is still safe if the trip
count is within range.
llvm-svn: 70421
This commit is contained in:
Dan Gohman
parent
8b1b8d5891
commit
06aff30f01
@ -718,7 +718,7 @@ SCEVHandle ScalarEvolution::getZeroExtendExpr(const SCEVHandle &Op,
|
||||
SCEVHandle BECount = getBackedgeTakenCount(AR->getLoop());
|
||||
if (!isa<SCEVCouldNotCompute>(BECount)) {
|
||||
// Manually compute the final value for AR, checking for
|
||||
// overflow at each step.
|
||||
// overflow.
|
||||
SCEVHandle Start = AR->getStart();
|
||||
SCEVHandle Step = AR->getStepRecurrence(*this);
|
||||
|
||||
@ -730,41 +730,34 @@ SCEVHandle ScalarEvolution::getZeroExtendExpr(const SCEVHandle &Op,
|
||||
getTruncateOrZeroExtend(CastedBECount, BECount->getType())) {
|
||||
const Type *WideTy =
|
||||
IntegerType::get(getTypeSizeInBits(Start->getType()) * 2);
|
||||
// Check whether Start+Step*BECount has no unsigned overflow.
|
||||
SCEVHandle ZMul =
|
||||
getMulExpr(CastedBECount,
|
||||
getTruncateOrZeroExtend(Step, Start->getType()));
|
||||
// Check whether Start+Step*BECount has no unsigned overflow.
|
||||
if (getZeroExtendExpr(ZMul, WideTy) ==
|
||||
getMulExpr(getZeroExtendExpr(CastedBECount, WideTy),
|
||||
getZeroExtendExpr(Step, WideTy))) {
|
||||
SCEVHandle Add = getAddExpr(Start, ZMul);
|
||||
if (getZeroExtendExpr(Add, WideTy) ==
|
||||
getAddExpr(getZeroExtendExpr(Start, WideTy),
|
||||
getZeroExtendExpr(ZMul, WideTy)))
|
||||
// Return the expression with the addrec on the outside.
|
||||
return getAddRecExpr(getZeroExtendExpr(Start, Ty),
|
||||
getZeroExtendExpr(Step, Ty),
|
||||
AR->getLoop());
|
||||
}
|
||||
SCEVHandle Add = getAddExpr(Start, ZMul);
|
||||
if (getZeroExtendExpr(Add, WideTy) ==
|
||||
getAddExpr(getZeroExtendExpr(Start, WideTy),
|
||||
getMulExpr(getZeroExtendExpr(CastedBECount, WideTy),
|
||||
getZeroExtendExpr(Step, WideTy))))
|
||||
// Return the expression with the addrec on the outside.
|
||||
return getAddRecExpr(getZeroExtendExpr(Start, Ty),
|
||||
getZeroExtendExpr(Step, Ty),
|
||||
AR->getLoop());
|
||||
|
||||
// Similar to above, only this time treat the step value as signed.
|
||||
// This covers loops that count down.
|
||||
SCEVHandle SMul =
|
||||
getMulExpr(CastedBECount,
|
||||
getTruncateOrSignExtend(Step, Start->getType()));
|
||||
// Check whether Start+Step*BECount has no unsigned overflow.
|
||||
if (getSignExtendExpr(SMul, WideTy) ==
|
||||
getMulExpr(getZeroExtendExpr(CastedBECount, WideTy),
|
||||
getSignExtendExpr(Step, WideTy))) {
|
||||
SCEVHandle Add = getAddExpr(Start, SMul);
|
||||
if (getZeroExtendExpr(Add, WideTy) ==
|
||||
getAddExpr(getZeroExtendExpr(Start, WideTy),
|
||||
getSignExtendExpr(SMul, WideTy)))
|
||||
// Return the expression with the addrec on the outside.
|
||||
return getAddRecExpr(getZeroExtendExpr(Start, Ty),
|
||||
getSignExtendExpr(Step, Ty),
|
||||
AR->getLoop());
|
||||
}
|
||||
Add = getAddExpr(Start, SMul);
|
||||
if (getZeroExtendExpr(Add, WideTy) ==
|
||||
getAddExpr(getZeroExtendExpr(Start, WideTy),
|
||||
getMulExpr(getZeroExtendExpr(CastedBECount, WideTy),
|
||||
getSignExtendExpr(Step, WideTy))))
|
||||
// Return the expression with the addrec on the outside.
|
||||
return getAddRecExpr(getZeroExtendExpr(Start, Ty),
|
||||
getSignExtendExpr(Step, Ty),
|
||||
AR->getLoop());
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -807,37 +800,31 @@ SCEVHandle ScalarEvolution::getSignExtendExpr(const SCEVHandle &Op,
|
||||
SCEVHandle BECount = getBackedgeTakenCount(AR->getLoop());
|
||||
if (!isa<SCEVCouldNotCompute>(BECount)) {
|
||||
// Manually compute the final value for AR, checking for
|
||||
// overflow at each step.
|
||||
// overflow.
|
||||
SCEVHandle Start = AR->getStart();
|
||||
SCEVHandle Step = AR->getStepRecurrence(*this);
|
||||
|
||||
// Check whether the backedge-taken count can be losslessly casted to
|
||||
// the addrec's type. The count needs to be the same whether sign
|
||||
// extended or zero extended.
|
||||
// the addrec's type. The count is always unsigned.
|
||||
SCEVHandle CastedBECount =
|
||||
getTruncateOrZeroExtend(BECount, Start->getType());
|
||||
if (BECount ==
|
||||
getTruncateOrZeroExtend(CastedBECount, BECount->getType()) &&
|
||||
BECount ==
|
||||
getTruncateOrSignExtend(CastedBECount, BECount->getType())) {
|
||||
getTruncateOrZeroExtend(CastedBECount, BECount->getType())) {
|
||||
const Type *WideTy =
|
||||
IntegerType::get(getTypeSizeInBits(Start->getType()) * 2);
|
||||
// Check whether Start+Step*BECount has no signed overflow.
|
||||
SCEVHandle SMul =
|
||||
getMulExpr(CastedBECount,
|
||||
getTruncateOrSignExtend(Step, Start->getType()));
|
||||
// Check whether Start+Step*BECount has no signed overflow.
|
||||
if (getSignExtendExpr(SMul, WideTy) ==
|
||||
getMulExpr(getSignExtendExpr(CastedBECount, WideTy),
|
||||
getSignExtendExpr(Step, WideTy))) {
|
||||
SCEVHandle Add = getAddExpr(Start, SMul);
|
||||
if (getSignExtendExpr(Add, WideTy) ==
|
||||
getAddExpr(getSignExtendExpr(Start, WideTy),
|
||||
getSignExtendExpr(SMul, WideTy)))
|
||||
// Return the expression with the addrec on the outside.
|
||||
return getAddRecExpr(getSignExtendExpr(Start, Ty),
|
||||
getSignExtendExpr(Step, Ty),
|
||||
AR->getLoop());
|
||||
}
|
||||
SCEVHandle Add = getAddExpr(Start, SMul);
|
||||
if (getSignExtendExpr(Add, WideTy) ==
|
||||
getAddExpr(getSignExtendExpr(Start, WideTy),
|
||||
getMulExpr(getZeroExtendExpr(CastedBECount, WideTy),
|
||||
getSignExtendExpr(Step, WideTy))))
|
||||
// Return the expression with the addrec on the outside.
|
||||
return getAddRecExpr(getSignExtendExpr(Start, Ty),
|
||||
getSignExtendExpr(Step, Ty),
|
||||
AR->getLoop());
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
31
test/Analysis/ScalarEvolution/sext-iv-0.ll
Normal file
31
test/Analysis/ScalarEvolution/sext-iv-0.ll
Normal file
@ -0,0 +1,31 @@
|
||||
; RUN: llvm-as < %s | opt -disable-output -scalar-evolution -analyze \
|
||||
; RUN: | grep { --> \{-128,+,1\}<bb1> Exits: 127} | count 5
|
||||
|
||||
; Convert (sext {-128,+,1}) to {sext(-128),+,sext(1)}, since the
|
||||
; trip count is within range where this is safe.
|
||||
|
||||
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"
|
||||
|
||||
define void @foo(double* nocapture %x) nounwind {
|
||||
bb1.thread:
|
||||
br label %bb1
|
||||
|
||||
bb1: ; preds = %bb1, %bb1.thread
|
||||
%i.0.reg2mem.0 = phi i64 [ -128, %bb1.thread ], [ %8, %bb1 ] ; <i64> [#uses=3]
|
||||
%0 = trunc i64 %i.0.reg2mem.0 to i8 ; <i8> [#uses=1]
|
||||
%1 = trunc i64 %i.0.reg2mem.0 to i9 ; <i8> [#uses=1]
|
||||
%2 = sext i9 %1 to i64 ; <i64> [#uses=1]
|
||||
%3 = getelementptr double* %x, i64 %2 ; <double*> [#uses=1]
|
||||
%4 = load double* %3, align 8 ; <double> [#uses=1]
|
||||
%5 = mul double %4, 3.900000e+00 ; <double> [#uses=1]
|
||||
%6 = sext i8 %0 to i64 ; <i64> [#uses=1]
|
||||
%7 = getelementptr double* %x, i64 %6 ; <double*> [#uses=1]
|
||||
store double %5, double* %7, align 8
|
||||
%8 = add i64 %i.0.reg2mem.0, 1 ; <i64> [#uses=2]
|
||||
%9 = icmp sgt i64 %8, 127 ; <i1> [#uses=1]
|
||||
br i1 %9, label %return, label %bb1
|
||||
|
||||
return: ; preds = %bb1
|
||||
ret void
|
||||
}
|
||||
100
test/Analysis/ScalarEvolution/sext-iv-1.ll
Normal file
100
test/Analysis/ScalarEvolution/sext-iv-1.ll
Normal file
@ -0,0 +1,100 @@
|
||||
; RUN: llvm-as < %s | opt -disable-output -scalar-evolution -analyze \
|
||||
; RUN: | grep { --> (sext i. \{.\*,+,.\*\}<bb1> to i64)} | count 5
|
||||
|
||||
; Don't convert (sext {...,+,...}) to {sext(...),+,sext(...)} in cases
|
||||
; where the trip count is not within range.
|
||||
|
||||
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"
|
||||
|
||||
define void @foo0(double* nocapture %x) nounwind {
|
||||
bb1.thread:
|
||||
br label %bb1
|
||||
|
||||
bb1: ; preds = %bb1, %bb1.thread
|
||||
%i.0.reg2mem.0 = phi i64 [ -128, %bb1.thread ], [ %8, %bb1 ] ; <i64> [#uses=3]
|
||||
%0 = trunc i64 %i.0.reg2mem.0 to i7 ; <i8> [#uses=1]
|
||||
%1 = trunc i64 %i.0.reg2mem.0 to i9 ; <i8> [#uses=1]
|
||||
%2 = sext i9 %1 to i64 ; <i64> [#uses=1]
|
||||
%3 = getelementptr double* %x, i64 %2 ; <double*> [#uses=1]
|
||||
%4 = load double* %3, align 8 ; <double> [#uses=1]
|
||||
%5 = mul double %4, 3.900000e+00 ; <double> [#uses=1]
|
||||
%6 = sext i7 %0 to i64 ; <i64> [#uses=1]
|
||||
%7 = getelementptr double* %x, i64 %6 ; <double*> [#uses=1]
|
||||
store double %5, double* %7, align 8
|
||||
%8 = add i64 %i.0.reg2mem.0, 1 ; <i64> [#uses=2]
|
||||
%9 = icmp sgt i64 %8, 127 ; <i1> [#uses=1]
|
||||
br i1 %9, label %return, label %bb1
|
||||
|
||||
return: ; preds = %bb1
|
||||
ret void
|
||||
}
|
||||
|
||||
define void @foo1(double* nocapture %x) nounwind {
|
||||
bb1.thread:
|
||||
br label %bb1
|
||||
|
||||
bb1: ; preds = %bb1, %bb1.thread
|
||||
%i.0.reg2mem.0 = phi i64 [ -128, %bb1.thread ], [ %8, %bb1 ] ; <i64> [#uses=3]
|
||||
%0 = trunc i64 %i.0.reg2mem.0 to i8 ; <i8> [#uses=1]
|
||||
%1 = trunc i64 %i.0.reg2mem.0 to i9 ; <i8> [#uses=1]
|
||||
%2 = sext i9 %1 to i64 ; <i64> [#uses=1]
|
||||
%3 = getelementptr double* %x, i64 %2 ; <double*> [#uses=1]
|
||||
%4 = load double* %3, align 8 ; <double> [#uses=1]
|
||||
%5 = mul double %4, 3.900000e+00 ; <double> [#uses=1]
|
||||
%6 = sext i8 %0 to i64 ; <i64> [#uses=1]
|
||||
%7 = getelementptr double* %x, i64 %6 ; <double*> [#uses=1]
|
||||
store double %5, double* %7, align 8
|
||||
%8 = add i64 %i.0.reg2mem.0, 1 ; <i64> [#uses=2]
|
||||
%9 = icmp sgt i64 %8, 128 ; <i1> [#uses=1]
|
||||
br i1 %9, label %return, label %bb1
|
||||
|
||||
return: ; preds = %bb1
|
||||
ret void
|
||||
}
|
||||
|
||||
define void @foo2(double* nocapture %x) nounwind {
|
||||
bb1.thread:
|
||||
br label %bb1
|
||||
|
||||
bb1: ; preds = %bb1, %bb1.thread
|
||||
%i.0.reg2mem.0 = phi i64 [ -129, %bb1.thread ], [ %8, %bb1 ] ; <i64> [#uses=3]
|
||||
%0 = trunc i64 %i.0.reg2mem.0 to i8 ; <i8> [#uses=1]
|
||||
%1 = trunc i64 %i.0.reg2mem.0 to i9 ; <i8> [#uses=1]
|
||||
%2 = sext i9 %1 to i64 ; <i64> [#uses=1]
|
||||
%3 = getelementptr double* %x, i64 %2 ; <double*> [#uses=1]
|
||||
%4 = load double* %3, align 8 ; <double> [#uses=1]
|
||||
%5 = mul double %4, 3.900000e+00 ; <double> [#uses=1]
|
||||
%6 = sext i8 %0 to i64 ; <i64> [#uses=1]
|
||||
%7 = getelementptr double* %x, i64 %6 ; <double*> [#uses=1]
|
||||
store double %5, double* %7, align 8
|
||||
%8 = add i64 %i.0.reg2mem.0, 1 ; <i64> [#uses=2]
|
||||
%9 = icmp sgt i64 %8, 127 ; <i1> [#uses=1]
|
||||
br i1 %9, label %return, label %bb1
|
||||
|
||||
return: ; preds = %bb1
|
||||
ret void
|
||||
}
|
||||
|
||||
define void @foo3(double* nocapture %x) nounwind {
|
||||
bb1.thread:
|
||||
br label %bb1
|
||||
|
||||
bb1: ; preds = %bb1, %bb1.thread
|
||||
%i.0.reg2mem.0 = phi i64 [ -128, %bb1.thread ], [ %8, %bb1 ] ; <i64> [#uses=3]
|
||||
%0 = trunc i64 %i.0.reg2mem.0 to i8 ; <i8> [#uses=1]
|
||||
%1 = trunc i64 %i.0.reg2mem.0 to i9 ; <i8> [#uses=1]
|
||||
%2 = sext i9 %1 to i64 ; <i64> [#uses=1]
|
||||
%3 = getelementptr double* %x, i64 %2 ; <double*> [#uses=1]
|
||||
%4 = load double* %3, align 8 ; <double> [#uses=1]
|
||||
%5 = mul double %4, 3.900000e+00 ; <double> [#uses=1]
|
||||
%6 = sext i8 %0 to i64 ; <i64> [#uses=1]
|
||||
%7 = getelementptr double* %x, i64 %6 ; <double*> [#uses=1]
|
||||
store double %5, double* %7, align 8
|
||||
%8 = add i64 %i.0.reg2mem.0, -1 ; <i64> [#uses=2]
|
||||
%9 = icmp sgt i64 %8, 127 ; <i1> [#uses=1]
|
||||
br i1 %9, label %return, label %bb1
|
||||
|
||||
return: ; preds = %bb1
|
||||
ret void
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user