[llvm] ebeef02 - [SCEV] Strenthen nowrap flags after constant folding for mul exprs
Nikita Popov via llvm-commits
llvm-commits at lists.llvm.org
Sun Oct 25 11:44:11 PDT 2020
Author: Nikita Popov
Date: 2020-10-25T19:43:58+01:00
New Revision: ebeef022aa6d244c3b151b247399e97e31d392ff
URL: https://github.com/llvm/llvm-project/commit/ebeef022aa6d244c3b151b247399e97e31d392ff
DIFF: https://github.com/llvm/llvm-project/commit/ebeef022aa6d244c3b151b247399e97e31d392ff.diff
LOG: [SCEV] Strenthen nowrap flags after constant folding for mul exprs
Same change as 0dda6333175c1749f12be660456ecedade3bcf21, but for
mul expressions. We want to first fold any constant operans and
then strengthen the nowrap flags, as we can compute more precise
flags at that point.
Added:
Modified:
llvm/lib/Analysis/ScalarEvolution.cpp
llvm/test/Analysis/IVUsers/quadradic-exit-value.ll
llvm/test/Analysis/LoopAccessAnalysis/wrapping-pointer-versioning.ll
llvm/test/Analysis/ScalarEvolution/zext-divrem.ll
llvm/test/Transforms/IndVarSimplify/ARM/code-size.ll
llvm/test/Transforms/IndVarSimplify/replace-loop-exit-folds.ll
Removed:
################################################################################
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index bce06acdf2e7..17f9c12921ef 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -2684,8 +2684,6 @@ const SCEV *ScalarEvolution::getMulExpr(SmallVectorImpl<const SCEV *> &Ops,
// Sort by complexity, this groups all similar expression types together.
GroupByComplexity(Ops, &LI, DT);
- Flags = StrengthenNoWrapFlags(this, scMulExpr, Ops, Flags);
-
// If there are any constants, fold them together.
unsigned Idx = 0;
if (const SCEVConstant *LHSC = dyn_cast<SCEVConstant>(Ops[0])) {
@@ -2713,6 +2711,8 @@ const SCEV *ScalarEvolution::getMulExpr(SmallVectorImpl<const SCEV *> &Ops,
return Ops[0];
}
+ Flags = StrengthenNoWrapFlags(this, scMulExpr, Ops, Flags);
+
// Limit recursion calls depth.
if (Depth > MaxArithDepth || hasHugeExpression(Ops))
return getOrCreateMulExpr(Ops, Flags);
diff --git a/llvm/test/Analysis/IVUsers/quadradic-exit-value.ll b/llvm/test/Analysis/IVUsers/quadradic-exit-value.ll
index 9135b669d18d..876b0bed4cbb 100644
--- a/llvm/test/Analysis/IVUsers/quadradic-exit-value.ll
+++ b/llvm/test/Analysis/IVUsers/quadradic-exit-value.ll
@@ -38,7 +38,7 @@ exit:
; sure they aren't marked as post-inc users.
;
; CHECK-LABEL: IV Users for loop %test1.loop
-; CHECK-NO-LCSSA: %sext.us = {0,+,(16777216 + (-16777216 * %sub.us))<nuw><nsw>,+,33554432}<%test1.loop> (post-inc with loop %test1.loop) in %f = ashr i32 %sext.us, 24
+; CHECK-NO-LCSSA: %sext.us = {0,+,(16777216 + (-16777216 * %sub.us)<nuw><nsw>)<nuw><nsw>,+,33554432}<%test1.loop> (post-inc with loop %test1.loop) in %f = ashr i32 %sext.us, 24
define i32 @test1(i1 %cond) {
entry:
%sub.us = select i1 %cond, i32 0, i32 0
diff --git a/llvm/test/Analysis/LoopAccessAnalysis/wrapping-pointer-versioning.ll b/llvm/test/Analysis/LoopAccessAnalysis/wrapping-pointer-versioning.ll
index 5d26e834e309..5b5c821e9983 100644
--- a/llvm/test/Analysis/LoopAccessAnalysis/wrapping-pointer-versioning.ll
+++ b/llvm/test/Analysis/LoopAccessAnalysis/wrapping-pointer-versioning.ll
@@ -122,7 +122,7 @@ for.end: ; preds = %for.body
; LAA: Memory dependences are safe{{$}}
; LAA: SCEV assumptions:
; LAA-NEXT: {(2 * (trunc i64 %N to i32)),+,-2}<%for.body> Added Flags: <nusw>
-; LAA-NEXT: {((4 * (zext i31 (trunc i64 %N to i31) to i64)) + %a),+,-4}<%for.body> Added Flags: <nusw>
+; LAA-NEXT: {((4 * (zext i31 (trunc i64 %N to i31) to i64))<nuw><nsw> + %a),+,-4}<%for.body> Added Flags: <nusw>
; The expression for %mul_ext as analyzed by SCEV is
; (zext i32 {(2 * (trunc i64 %N to i32)),+,-2}<%for.body> to i64)
@@ -131,7 +131,7 @@ for.end: ; preds = %for.body
; LAA: [PSE] %arrayidxA = getelementptr i16, i16* %a, i64 %mul_ext:
; LAA-NEXT: ((2 * (zext i32 {(2 * (trunc i64 %N to i32)),+,-2}<%for.body> to i64))<nuw><nsw> + %a)
-; LAA-NEXT: --> {((4 * (zext i31 (trunc i64 %N to i31) to i64)) + %a),+,-4}<%for.body>
+; LAA-NEXT: --> {((4 * (zext i31 (trunc i64 %N to i31) to i64))<nuw><nsw> + %a),+,-4}<%for.body>
; LV-LABEL: f2
; LV-LABEL: for.body.lver.check
diff --git a/llvm/test/Analysis/ScalarEvolution/zext-divrem.ll b/llvm/test/Analysis/ScalarEvolution/zext-divrem.ll
index 3e5f3b0f5485..889fbabc81c4 100644
--- a/llvm/test/Analysis/ScalarEvolution/zext-divrem.ll
+++ b/llvm/test/Analysis/ScalarEvolution/zext-divrem.ll
@@ -38,6 +38,6 @@ define i64 @test4(i32 %t) {
%sub = sub i32 %a, %mul
%zext = zext i32 %sub to i64
; CHECK: %zext
-; CHECK-NEXT: --> ((-56 * ((zext i32 %t to i64) /u 112)) + ((zext i32 %t to i64) /u 2))
+; CHECK-NEXT: --> ((-56 * ((zext i32 %t to i64) /u 112))<nsw> + ((zext i32 %t to i64) /u 2))
ret i64 %zext
}
diff --git a/llvm/test/Transforms/IndVarSimplify/ARM/code-size.ll b/llvm/test/Transforms/IndVarSimplify/ARM/code-size.ll
index 4c5f9ef05bad..bf5f6b3f0e9b 100644
--- a/llvm/test/Transforms/IndVarSimplify/ARM/code-size.ll
+++ b/llvm/test/Transforms/IndVarSimplify/ARM/code-size.ll
@@ -10,7 +10,7 @@ define i32 @remove_loop(i32 %size) #0 {
; CHECK-V8M-NEXT: [[UMIN:%.*]] = select i1 [[TMP1]], i32 [[SIZE]], i32 31
; CHECK-V8M-NEXT: [[TMP2:%.*]] = sub i32 [[TMP0]], [[UMIN]]
; CHECK-V8M-NEXT: [[TMP3:%.*]] = lshr i32 [[TMP2]], 5
-; CHECK-V8M-NEXT: [[TMP4:%.*]] = shl i32 [[TMP3]], 5
+; CHECK-V8M-NEXT: [[TMP4:%.*]] = shl nuw i32 [[TMP3]], 5
; CHECK-V8M-NEXT: br label [[WHILE_COND:%.*]]
; CHECK-V8M: while.cond:
; CHECK-V8M-NEXT: br i1 false, label [[WHILE_COND]], label [[WHILE_END:%.*]]
@@ -25,7 +25,7 @@ define i32 @remove_loop(i32 %size) #0 {
; CHECK-V8A-NEXT: [[UMIN:%.*]] = select i1 [[TMP1]], i32 [[SIZE]], i32 31
; CHECK-V8A-NEXT: [[TMP2:%.*]] = sub i32 [[TMP0]], [[UMIN]]
; CHECK-V8A-NEXT: [[TMP3:%.*]] = lshr i32 [[TMP2]], 5
-; CHECK-V8A-NEXT: [[TMP4:%.*]] = shl i32 [[TMP3]], 5
+; CHECK-V8A-NEXT: [[TMP4:%.*]] = shl nuw i32 [[TMP3]], 5
; CHECK-V8A-NEXT: br label [[WHILE_COND:%.*]]
; CHECK-V8A: while.cond:
; CHECK-V8A-NEXT: br i1 false, label [[WHILE_COND]], label [[WHILE_END:%.*]]
diff --git a/llvm/test/Transforms/IndVarSimplify/replace-loop-exit-folds.ll b/llvm/test/Transforms/IndVarSimplify/replace-loop-exit-folds.ll
index 9cc911cc5a0d..e7512757ab57 100644
--- a/llvm/test/Transforms/IndVarSimplify/replace-loop-exit-folds.ll
+++ b/llvm/test/Transforms/IndVarSimplify/replace-loop-exit-folds.ll
@@ -8,10 +8,10 @@ define i32 @remove_loop(i32 %size) {
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[SIZE:%.*]], 31
; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i32 [[SIZE]], 31
-; CHECK-NEXT: [[UMAX:%.*]] = select i1 [[TMP1]], i32 [[SIZE]], i32 31
-; CHECK-NEXT: [[TMP2:%.*]] = sub i32 [[TMP0]], [[UMAX]]
+; CHECK-NEXT: [[UMIN:%.*]] = select i1 [[TMP1]], i32 [[SIZE]], i32 31
+; CHECK-NEXT: [[TMP2:%.*]] = sub i32 [[TMP0]], [[UMIN]]
; CHECK-NEXT: [[TMP3:%.*]] = lshr i32 [[TMP2]], 5
-; CHECK-NEXT: [[TMP4:%.*]] = shl i32 [[TMP3]], 5
+; CHECK-NEXT: [[TMP4:%.*]] = shl nuw i32 [[TMP3]], 5
; CHECK-NEXT: br label [[WHILE_COND:%.*]]
; CHECK: while.cond:
; CHECK-NEXT: [[SIZE_ADDR_0:%.*]] = phi i32 [ [[SIZE]], [[ENTRY:%.*]] ], [ [[SUB:%.*]], [[WHILE_COND]] ]
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