[llvm] 45555c3 - [InstSimplify] Simplify calls with "returned" attribute
Nikita Popov via llvm-commits
llvm-commits at lists.llvm.org
Mon Mar 9 10:54:16 PDT 2020
Author: Nikita Popov
Date: 2020-03-09T18:53:47+01:00
New Revision: 45555c381926050bc45a3372b1af0e15650371b6
URL: https://github.com/llvm/llvm-project/commit/45555c381926050bc45a3372b1af0e15650371b6
DIFF: https://github.com/llvm/llvm-project/commit/45555c381926050bc45a3372b1af0e15650371b6.diff
LOG: [InstSimplify] Simplify calls with "returned" attribute
If a call argument has the "returned" attribute, we can simplify
the call to the value of that argument. The "-inst-simplify" pass
already handled this for the constant integer argument case via
known bits, which is invoked in SimplifyInstruction. However,
non-constant (or non-int) arguments are not handled at all right now.
This addresses one of the regressions from D75801.
Differential Revision: https://reviews.llvm.org/D75815
Added:
Modified:
llvm/lib/Analysis/InstructionSimplify.cpp
llvm/test/Analysis/ValueTracking/known-nonnull-at.ll
llvm/test/Transforms/InstCombine/align-attr.ll
llvm/test/Transforms/InstCombine/expensive-combines.ll
llvm/test/Transforms/InstCombine/fortify-folding.ll
llvm/test/Transforms/InstCombine/strcpy_chk-1.ll
llvm/test/Transforms/InstCombine/strncpy_chk-1.ll
llvm/test/Transforms/InstCombine/unused-nonnull.ll
llvm/test/Transforms/InstSimplify/call.ll
Removed:
################################################################################
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index 3b80e535f85b..47f034017c48 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -5348,6 +5348,9 @@ Value *llvm::SimplifyCall(CallBase *Call, const SimplifyQuery &Q) {
if (Value *Ret = simplifyIntrinsic(Call, Q))
return Ret;
+ if (Value *ReturnedArg = Call->getReturnedArgOperand())
+ return ReturnedArg;
+
if (!canConstantFoldCallTo(Call, F))
return nullptr;
diff --git a/llvm/test/Analysis/ValueTracking/known-nonnull-at.ll b/llvm/test/Analysis/ValueTracking/known-nonnull-at.ll
index 9df8c2855132..06f481183781 100644
--- a/llvm/test/Analysis/ValueTracking/known-nonnull-at.ll
+++ b/llvm/test/Analysis/ValueTracking/known-nonnull-at.ll
@@ -117,7 +117,7 @@ define i1 @nonnullReturnTest(i8* nonnull %x) {
define i1 @unknownReturnTest(i8* %x) {
; CHECK-LABEL: @unknownReturnTest(
; CHECK-NEXT: [[X2:%.*]] = call i8* @returningPtr(i8* [[X:%.*]])
-; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[X2]], null
+; CHECK-NEXT: [[NULL_CHECK:%.*]] = icmp eq i8* [[X]], null
; CHECK-NEXT: ret i1 [[NULL_CHECK]]
;
%x2 = call i8* @returningPtr(i8* %x)
diff --git a/llvm/test/Transforms/InstCombine/align-attr.ll b/llvm/test/Transforms/InstCombine/align-attr.ll
index 16782dba2eff..2b004311cc8e 100644
--- a/llvm/test/Transforms/InstCombine/align-attr.ll
+++ b/llvm/test/Transforms/InstCombine/align-attr.ll
@@ -20,7 +20,7 @@ define i32 @foo2(i32* align 32 %a) #0 {
; CHECK-LABEL: @foo2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[V:%.*]] = call i32* @func1(i32* [[A:%.*]])
-; CHECK-NEXT: [[TMP0:%.*]] = load i32, i32* [[V]], align 32
+; CHECK-NEXT: [[TMP0:%.*]] = load i32, i32* [[A]], align 32
; CHECK-NEXT: ret i32 [[TMP0]]
;
entry:
diff --git a/llvm/test/Transforms/InstCombine/expensive-combines.ll b/llvm/test/Transforms/InstCombine/expensive-combines.ll
index 28acb773bfd5..96a45b05cfb5 100644
--- a/llvm/test/Transforms/InstCombine/expensive-combines.ll
+++ b/llvm/test/Transforms/InstCombine/expensive-combines.ll
@@ -16,7 +16,7 @@ define void @test() {
;
; EXPENSIVE-OFF-LABEL: @test(
; EXPENSIVE-OFF-NEXT: [[CALL:%.*]] = call i32 @passthru(i32 0)
-; EXPENSIVE-OFF-NEXT: call void @sink(i32 [[CALL]])
+; EXPENSIVE-OFF-NEXT: call void @sink(i32 0)
; EXPENSIVE-OFF-NEXT: ret void
;
%call = call i32 @passthru(i32 0)
diff --git a/llvm/test/Transforms/InstCombine/fortify-folding.ll b/llvm/test/Transforms/InstCombine/fortify-folding.ll
index ee81557615a5..b2171a44f57e 100644
--- a/llvm/test/Transforms/InstCombine/fortify-folding.ll
+++ b/llvm/test/Transforms/InstCombine/fortify-folding.ll
@@ -82,7 +82,7 @@ define i32 @test_not_sprintf() {
define i8* @test_strcat() {
; CHECK-LABEL: @test_strcat(
; CHECK-NEXT: [[STRCAT:%.*]] = call i8* @strcat(i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @a, i64 0, i64 0), i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @b, i64 0, i64 0))
-; CHECK-NEXT: ret i8* [[STRCAT]]
+; CHECK-NEXT: ret i8* getelementptr inbounds ([60 x i8], [60 x i8]* @a, i64 0, i64 0)
;
%dst = getelementptr inbounds [60 x i8], [60 x i8]* @a, i32 0, i32 0
%src = getelementptr inbounds [60 x i8], [60 x i8]* @b, i32 0, i32 0
@@ -126,7 +126,7 @@ define i64 @test_not_strlcat() {
define i8* @test_strncat() {
; CHECK-LABEL: @test_strncat(
; CHECK-NEXT: [[STRNCAT:%.*]] = call i8* @strncat(i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @a, i64 0, i64 0), i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @b, i64 0, i64 0), i64 22)
-; CHECK-NEXT: ret i8* [[STRNCAT]]
+; CHECK-NEXT: ret i8* getelementptr inbounds ([60 x i8], [60 x i8]* @a, i64 0, i64 0)
;
%dst = getelementptr inbounds [60 x i8], [60 x i8]* @a, i32 0, i32 0
%src = getelementptr inbounds [60 x i8], [60 x i8]* @b, i32 0, i32 0
diff --git a/llvm/test/Transforms/InstCombine/strcpy_chk-1.ll b/llvm/test/Transforms/InstCombine/strcpy_chk-1.ll
index 02a4b5cbdeac..67e393d1525b 100644
--- a/llvm/test/Transforms/InstCombine/strcpy_chk-1.ll
+++ b/llvm/test/Transforms/InstCombine/strcpy_chk-1.ll
@@ -53,7 +53,7 @@ define i8* @test_simplify3() {
define i8* @test_simplify4() {
; CHECK-LABEL: @test_simplify4(
; CHECK-NEXT: [[STRCPY:%.*]] = call i8* @strcpy(i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @a, i32 0, i32 0), i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @b, i32 0, i32 0))
-; CHECK-NEXT: ret i8* [[STRCPY]]
+; CHECK-NEXT: ret i8* getelementptr inbounds ([60 x i8], [60 x i8]* @a, i32 0, i32 0)
;
%dst = getelementptr inbounds [60 x i8], [60 x i8]* @a, i32 0, i32 0
%src = getelementptr inbounds [60 x i8], [60 x i8]* @b, i32 0, i32 0
diff --git a/llvm/test/Transforms/InstCombine/strncpy_chk-1.ll b/llvm/test/Transforms/InstCombine/strncpy_chk-1.ll
index ed90303b2808..7601b1669359 100644
--- a/llvm/test/Transforms/InstCombine/strncpy_chk-1.ll
+++ b/llvm/test/Transforms/InstCombine/strncpy_chk-1.ll
@@ -39,7 +39,7 @@ define i8* @test_simplify2() {
define i8* @test_simplify3() {
; CHECK-LABEL: @test_simplify3(
; CHECK-NEXT: [[STRNCPY:%.*]] = call i8* @strncpy(i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @a, i32 0, i32 0), i8* nonnull dereferenceable(1) getelementptr inbounds ([60 x i8], [60 x i8]* @b, i32 0, i32 0), i32 12)
-; CHECK-NEXT: ret i8* [[STRNCPY]]
+; CHECK-NEXT: ret i8* getelementptr inbounds ([60 x i8], [60 x i8]* @a, i32 0, i32 0)
;
%dst = getelementptr inbounds [60 x i8], [60 x i8]* @a, i32 0, i32 0
%src = getelementptr inbounds [60 x i8], [60 x i8]* @b, i32 0, i32 0
diff --git a/llvm/test/Transforms/InstCombine/unused-nonnull.ll b/llvm/test/Transforms/InstCombine/unused-nonnull.ll
index 0a1520ea73c2..382d2634b86c 100644
--- a/llvm/test/Transforms/InstCombine/unused-nonnull.ll
+++ b/llvm/test/Transforms/InstCombine/unused-nonnull.ll
@@ -12,13 +12,8 @@ define i32 @main(i32 %argc, i8** %argv) #0 {
; CHECK-SAME: (i32 [[ARGC:%.*]], i8** nocapture readnone [[ARGV:%.*]]) local_unnamed_addr #0
; CHECK-NEXT: entry:
; CHECK-NEXT: [[TMP0:%.*]] = icmp slt i32 [[ARGC]], 2
-; CHECK-NEXT: br i1 [[TMP0]], label [[DONE:%.*]], label [[DO_WORK:%.*]]
-; CHECK: do_work:
-; CHECK-NEXT: [[TMP1:%.*]] = tail call i32 @compute(i8* undef, i32 [[ARGC]])
-; CHECK-NEXT: br label [[DONE]]
-; CHECK: done:
-; CHECK-NEXT: [[RETVAL:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[TMP1]], [[DO_WORK]] ]
-; CHECK-NEXT: ret i32 [[RETVAL]]
+; CHECK-NEXT: [[SPEC_SELECT:%.*]] = select i1 [[TMP0]], i32 0, i32 [[ARGC]]
+; CHECK-NEXT: ret i32 [[SPEC_SELECT]]
;
entry:
%0 = getelementptr inbounds i8*, i8** %argv, i32 0
diff --git a/llvm/test/Transforms/InstSimplify/call.ll b/llvm/test/Transforms/InstSimplify/call.ll
index 108de9082a70..d744db6ddf76 100644
--- a/llvm/test/Transforms/InstSimplify/call.ll
+++ b/llvm/test/Transforms/InstSimplify/call.ll
@@ -993,7 +993,7 @@ define i32 @returned_const_int_arg() {
define i8* @returned_const_ptr_arg() {
; CHECK-LABEL: @returned_const_ptr_arg(
; CHECK-NEXT: [[X:%.*]] = call i8* @passthru_p8(i8* null)
-; CHECK-NEXT: ret i8* [[X]]
+; CHECK-NEXT: ret i8* null
;
%x = call i8* @passthru_p8(i8* null)
ret i8* %x
@@ -1002,7 +1002,7 @@ define i8* @returned_const_ptr_arg() {
define i32 @returned_var_arg(i32 %arg) {
; CHECK-LABEL: @returned_var_arg(
; CHECK-NEXT: [[X:%.*]] = call i32 @passthru_i32(i32 [[ARG:%.*]])
-; CHECK-NEXT: ret i32 [[X]]
+; CHECK-NEXT: ret i32 [[ARG]]
;
%x = call i32 @passthru_i32(i32 %arg)
ret i32 %x
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