[polly] a2619a6 - Reland "[ScalarEvolution] createSCEV(): recognize `udiv`/`urem` disguised as an `sdiv`/`srem`"
Roman Lebedev via llvm-commits
llvm-commits at lists.llvm.org
Mon Jul 6 08:00:40 PDT 2020
Author: Roman Lebedev
Date: 2020-07-06T18:00:22+03:00
New Revision: a2619a60e4601c445e9ca6e16c76052e00d907ff
URL: https://github.com/llvm/llvm-project/commit/a2619a60e4601c445e9ca6e16c76052e00d907ff
DIFF: https://github.com/llvm/llvm-project/commit/a2619a60e4601c445e9ca6e16c76052e00d907ff.diff
LOG: Reland "[ScalarEvolution] createSCEV(): recognize `udiv`/`urem` disguised as an `sdiv`/`srem`"
This reverts commit d3e3f36ff1151f565730977ac4f663a2ccee48ae,
which reverter the original commit 2c16100e6f72075564ea1f67fa5a82c269dafcd3,
but with polly tests now actually passing.
Added:
Modified:
llvm/lib/Analysis/ScalarEvolution.cpp
llvm/test/Analysis/ScalarEvolution/sdiv.ll
llvm/test/Analysis/ScalarEvolution/srem.ll
polly/test/Isl/CodeGen/MemAccess/generate-all.ll
polly/test/ScopInfo/multidim_srem.ll
Removed:
################################################################################
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 609ad639d9c0..75926aa3a960 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -6303,6 +6303,20 @@ const SCEV *ScalarEvolution::createSCEV(Value *V) {
return getSCEV(U->getOperand(0));
break;
+ case Instruction::SDiv:
+ // If both operands are non-negative, this is just an udiv.
+ if (isKnownNonNegative(getSCEV(U->getOperand(0))) &&
+ isKnownNonNegative(getSCEV(U->getOperand(1))))
+ return getUDivExpr(getSCEV(U->getOperand(0)), getSCEV(U->getOperand(1)));
+ break;
+
+ case Instruction::SRem:
+ // If both operands are non-negative, this is just an urem.
+ if (isKnownNonNegative(getSCEV(U->getOperand(0))) &&
+ isKnownNonNegative(getSCEV(U->getOperand(1))))
+ return getURemExpr(getSCEV(U->getOperand(0)), getSCEV(U->getOperand(1)));
+ break;
+
// It's tempting to handle inttoptr and ptrtoint as no-ops, however this can
// lead to pointer expressions which cannot safely be expanded to GEPs,
// because ScalarEvolution doesn't respect the GEP aliasing rules when
diff --git a/llvm/test/Analysis/ScalarEvolution/sdiv.ll b/llvm/test/Analysis/ScalarEvolution/sdiv.ll
index b4895855ab71..106cda1b7f0f 100644
--- a/llvm/test/Analysis/ScalarEvolution/sdiv.ll
+++ b/llvm/test/Analysis/ScalarEvolution/sdiv.ll
@@ -14,11 +14,11 @@ define dso_local void @_Z4loopi(i32 %width) local_unnamed_addr #0 {
; CHECK-NEXT: %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
; CHECK-NEXT: --> {0,+,1}<nuw><nsw><%for.cond> U: [0,-2147483648) S: [0,-2147483648) Exits: %width LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %rem = sdiv i32 %i.0, 2
-; CHECK-NEXT: --> %rem U: full-set S: [-1073741824,1073741824) Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
+; CHECK-NEXT: --> ({0,+,1}<nuw><nsw><%for.cond> /u 2) U: [0,1073741824) S: [0,1073741824) Exits: (%width /u 2) LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %idxprom = sext i32 %rem to i64
-; CHECK-NEXT: --> (sext i32 %rem to i64) U: [-2147483648,2147483648) S: [-1073741824,1073741824) Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
+; CHECK-NEXT: --> ({0,+,1}<nuw><nsw><%for.cond> /u 2) U: [0,2147483648) S: [0,2147483648) Exits: ((zext i32 %width to i64) /u 2) LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %arrayidx = getelementptr inbounds [2 x i32], [2 x i32]* %storage, i64 0, i64 %idxprom
-; CHECK-NEXT: --> ((4 * (sext i32 %rem to i64))<nsw> + %storage)<nsw> U: [0,-3) S: [-9223372036854775808,9223372036854775805) Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
+; CHECK-NEXT: --> ((4 * ({0,+,1}<nuw><nsw><%for.cond> /u 2))<nuw><nsw> + %storage)<nsw> U: [0,-3) S: [-9223372036854775808,9223372036854775805) Exits: ((4 * ((zext i32 %width to i64) /u 2))<nuw><nsw> + %storage)<nsw> LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %1 = load i32, i32* %arrayidx, align 4
; CHECK-NEXT: --> %1 U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
; CHECK-NEXT: %call = call i32 @_Z3adji(i32 %1)
diff --git a/llvm/test/Analysis/ScalarEvolution/srem.ll b/llvm/test/Analysis/ScalarEvolution/srem.ll
index 365b40d88e24..6debab34e3b3 100644
--- a/llvm/test/Analysis/ScalarEvolution/srem.ll
+++ b/llvm/test/Analysis/ScalarEvolution/srem.ll
@@ -14,11 +14,11 @@ define dso_local void @_Z4loopi(i32 %width) local_unnamed_addr #0 {
; CHECK-NEXT: %i.0 = phi i32 [ 0, %entry ], [ %inc, %for.body ]
; CHECK-NEXT: --> {0,+,1}<nuw><nsw><%for.cond> U: [0,-2147483648) S: [0,-2147483648) Exits: %width LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %rem = srem i32 %i.0, 2
-; CHECK-NEXT: --> %rem U: [0,2) S: [-2,2) Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
+; CHECK-NEXT: --> (zext i1 {false,+,true}<%for.cond> to i32) U: [0,2) S: [0,2) Exits: (zext i1 (trunc i32 %width to i1) to i32) LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %idxprom = sext i32 %rem to i64
-; CHECK-NEXT: --> (sext i32 %rem to i64) U: [0,2) S: [-2,2) Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
+; CHECK-NEXT: --> (zext i1 {false,+,true}<%for.cond> to i64) U: [0,2) S: [0,2) Exits: (zext i1 (trunc i32 %width to i1) to i64) LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %arrayidx = getelementptr inbounds [2 x i32], [2 x i32]* %storage, i64 0, i64 %idxprom
-; CHECK-NEXT: --> ((4 * (sext i32 %rem to i64))<nuw><nsw> + %storage)<nsw> U: [0,-3) S: [-9223372036854775808,9223372036854775805) Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
+; CHECK-NEXT: --> ((4 * (zext i1 {false,+,true}<%for.cond> to i64))<nuw><nsw> + %storage)<nsw> U: [0,-3) S: [-9223372036854775808,9223372036854775805) Exits: ((4 * (zext i1 (trunc i32 %width to i1) to i64))<nuw><nsw> + %storage)<nsw> LoopDispositions: { %for.cond: Computable }
; CHECK-NEXT: %1 = load i32, i32* %arrayidx, align 4
; CHECK-NEXT: --> %1 U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %for.cond: Variant }
; CHECK-NEXT: %call = call i32 @_Z3adji(i32 %1)
diff --git a/polly/test/Isl/CodeGen/MemAccess/generate-all.ll b/polly/test/Isl/CodeGen/MemAccess/generate-all.ll
index a3253ef2d168..f9b07a947c6a 100644
--- a/polly/test/Isl/CodeGen/MemAccess/generate-all.ll
+++ b/polly/test/Isl/CodeGen/MemAccess/generate-all.ll
@@ -9,11 +9,12 @@
; }
; SCEV: polly.stmt.bb2: ; preds = %polly.loop_header
-; SCEV-NEXT: %p_tmp = srem i64 %polly.indvar, 4
-; SCEV-NEXT: %p_tmp3 = getelementptr inbounds float, float* %A, i64 %p_tmp
-; SCEV-NEXT: %tmp4_p_scalar_ = load float, float* %p_tmp3, align 4, !alias.scope !0, !noalias !2
+; SCEV-NEXT: %0 = trunc i64 %polly.indvar to i2
+; SCEV-NEXT: %1 = zext i2 %0 to i64
+; SCEV-NEXT: %scevgep = getelementptr float, float* %A, i64 %1
+; SCEV-NEXT: %tmp4_p_scalar_ = load float, float* %scevgep, align 4, !alias.scope !0, !noalias !2
; SCEV-NEXT: %p_tmp5 = fadd float %tmp4_p_scalar_, 1.000000e+01
-; SCEV-NEXT: store float %p_tmp5, float* %p_tmp3, align 4, !alias.scope !0, !noalias !2
+; SCEV-NEXT: store float %p_tmp5, float* %scevgep, align 4, !alias.scope !0, !noalias !2
; SCEV-NEXT: %polly.indvar_next = add nsw i64 %polly.indvar, 1
; SCEV-NEXT: %polly.loop_cond = icmp sle i64 %polly.indvar_next, 99
; SCEV-NEXT: br i1 %polly.loop_cond, label %polly.loop_header, label %polly.loop_exit
diff --git a/polly/test/ScopInfo/multidim_srem.ll b/polly/test/ScopInfo/multidim_srem.ll
index 10673f41aaee..f7f9616a9df3 100644
--- a/polly/test/ScopInfo/multidim_srem.ll
+++ b/polly/test/ScopInfo/multidim_srem.ll
@@ -14,11 +14,12 @@
; CHECK-NEXT: Schedule :=
; CHECK-NEXT: [n] -> { Stmt_for_body_8[i0, i1, i2] -> [i0, i1, i2] };
; CHECK-NEXT: ReadAccess := [Reduction Type: NONE] [Scalar: 0]
-; CHECK-NEXT: [n] -> { Stmt_for_body_8[i0, i1, i2] -> MemRef_A[o0, i1, i2] : (i0 + o0) mod 2 = 0 and 0 <= o0 <= 1 }
+; CHECK-NEXT: [n] -> { Stmt_for_body_8[i0, i1, i2] -> MemRef_A[1, i1, i2] : (1 + i0) mod 2 = 0; Stmt_for_body_8[i0, i1, i2] -> MemRef_A[0, i1, i2] : (i0) mod 2 = 0 };
; CHECK-NEXT: MustWriteAccess := [Reduction Type: NONE] [Scalar: 0]
-; CHECK-NEXT: [n] -> { Stmt_for_body_8[i0, i1, i2] -> MemRef_A[o0, i1, i2] : (i0 + o0) mod 2 = 0 and 0 <= o0 <= 1 };
+; CHECK-NEXT: [n] -> { Stmt_for_body_8[i0, i1, i2] -> MemRef_A[1, i1, i2] : (1 + i0) mod 2 = 0; Stmt_for_body_8[i0, i1, i2] -> MemRef_A[0, i1, i2] : (i0) mod 2 = 0 };
; CHECK-NEXT: }
+
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
More information about the llvm-commits
mailing list