[llvm] r290423 - [framelowering] Skip dbg values when getting next/previous instruction.
Florian Hahn via llvm-commits
llvm-commits at lists.llvm.org
Fri Dec 23 03:35:00 PST 2016
Author: fhahn
Date: Fri Dec 23 05:35:00 2016
New Revision: 290423
URL: http://llvm.org/viewvc/llvm-project?rev=290423&view=rev
Log:
[framelowering] Skip dbg values when getting next/previous instruction.
Summary:
In mergeSPUpdates, debug values need to be ignored when getting the
previous element, otherwise debug data could have an impact on codegen.
In eliminateCallFramePseudoInstr, debug values after the erased element
could have an impact on codegen and should be skipped.
Closes PR31319 (https://llvm.org/bugs/show_bug.cgi?id=31319)
Reviewers: mkuper, MatzeB, aprantl
Subscribers: gbedwell, llvm-commits
Differential Revision: https://reviews.llvm.org/D27688
Added:
llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic-2.ll
Modified:
llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic.ll
Modified: llvm/trunk/lib/Target/X86/X86FrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86FrameLowering.cpp?rev=290423&r1=290422&r2=290423&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86FrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86FrameLowering.cpp Fri Dec 23 05:35:00 2016
@@ -373,6 +373,10 @@ int X86FrameLowering::mergeSPUpdates(Mac
MachineBasicBlock::iterator PI = doMergeWithPrevious ? std::prev(MBBI) : MBBI;
MachineBasicBlock::iterator NI = doMergeWithPrevious ? nullptr
: std::next(MBBI);
+ PI = skipDebugInstructionsBackward(PI, MBB.begin());
+ if (NI != nullptr)
+ NI = skipDebugInstructionsForward(NI, MBB.end());
+
unsigned Opc = PI->getOpcode();
int Offset = 0;
@@ -2586,6 +2590,7 @@ eliminateCallFramePseudoInstr(MachineFun
uint64_t Amount = !reserveCallFrame ? I->getOperand(0).getImm() : 0;
uint64_t InternalAmt = (isDestroy || Amount) ? I->getOperand(1).getImm() : 0;
I = MBB.erase(I);
+ I = skipDebugInstructionsForward(I, MBB.end());
if (!reserveCallFrame) {
// If the stack pointer can be changed after prologue, turn the
Added: llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic-2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic-2.ll?rev=290423&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic-2.ll (added)
+++ llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic-2.ll Fri Dec 23 05:35:00 2016
@@ -0,0 +1,72 @@
+; Test ensuring debug intrinsics do not affect generated function prologue.
+;
+; RUN: llc -O1 -mtriple=x86_64-unknown-unknown -o - %s | FileCheck %s
+
+ at a = local_unnamed_addr global i64 0, align 8
+
+define void @noDebug() {
+entry:
+ %0 = load i64, i64* @a, align 8
+ %1 = load i64, i64* @a, align 8
+ %2 = load i64, i64* @a, align 8
+ %3 = tail call { i64, i1 } @llvm.uadd.with.overflow.i64(i64 %0, i64 %1)
+ %4 = extractvalue { i64, i1 } %3, 0
+ %5 = tail call i64 @fn1(i64 %4, i64 %2)
+ tail call void (...) @printf()
+ tail call void (...) @printf(i64 1, i64 2, i64 3, i64 4, i32 0, i64 0, i64 %4, i64 %5)
+ ret void
+}
+
+; CHECK-LABEL: noDebug
+; CHECK: addq $24, %rsp
+; CHECK: popq %rbx
+; CHECK-NEXT: popq %r14
+; CHECK-NEXT: retq
+
+
+define void @withDebug() !dbg !18 {
+entry:
+ %0 = load i64, i64* @a, align 8
+ %1 = load i64, i64* @a, align 8
+ %2 = load i64, i64* @a, align 8
+ %3 = tail call { i64, i1 } @llvm.uadd.with.overflow.i64(i64 %0, i64 %1)
+ %4 = extractvalue { i64, i1 } %3, 0
+ %5 = tail call i64 @fn1(i64 %4, i64 %2)
+ tail call void @llvm.dbg.value(metadata i64 %4, i64 0, metadata !23, metadata !33), !dbg !34
+ tail call void @llvm.dbg.value(metadata i64 %5, i64 0, metadata !22, metadata !33), !dbg !35
+ tail call void (...) @printf()
+ tail call void (...) @printf(i64 1, i64 2, i64 3, i64 4, i32 0, i64 0, i64 %4, i64 %5)
+ ret void
+}
+
+; CHECK-LABEL: withDebug
+; CHECK: #DEBUG_VALUE: test:j <- %RBX
+; CHECK-NEXT: addq $24, %rsp
+; CHECK: popq %rbx
+; CHECK-NEXT: popq %r14
+; CHECK-NEXT: retq
+
+declare { i64, i1 } @llvm.uadd.with.overflow.i64(i64, i64)
+declare i64 @fn1(i64, i64)
+
+declare void @printf(...)
+
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata)
+
+
+!llvm.dbg.cu = !{!1}
+!llvm.module.flags = !{!15, !16}
+
+!1 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !2, producer: "clang version 4.0.0")
+!2 = !DIFile(filename: "test.cpp", directory: "")
+!11 = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
+!15 = !{i32 2, !"Dwarf Version", i32 4}
+!16 = !{i32 2, !"Debug Info Version", i32 3}
+!18 = distinct !DISubprogram(name: "test", scope: !2, file: !2, line: 5, unit: !1)
+!22 = !DILocalVariable(name: "i", scope: !18, file: !2, line: 6, type: !11)
+!23 = !DILocalVariable(name: "j", scope: !18, file: !2, line: 7, type: !11)
+!33 = !DIExpression()
+!34 = !DILocation(line: 7, column: 17, scope: !18)
+!35 = !DILocation(line: 6, column: 8, scope: !18)
+!36 = !DILocation(line: 9, column: 3, scope: !18)
+!37 = !DILocation(line: 10, column: 10, scope: !18)
Modified: llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic.ll?rev=290423&r1=290422&r2=290423&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic.ll (original)
+++ llvm/trunk/test/CodeGen/X86/frame-lowering-debug-intrinsic.ll Fri Dec 23 05:35:00 2016
@@ -2,31 +2,56 @@
;
; RUN: llc -O1 -mtriple=x86_64-unknown-unknown -o - %s | FileCheck %s
-
-define i64 @noDebug(i64 %a) {
+define i64 @fn1NoDebug(i64 %a) {
%call = call i64 @fn(i64 %a, i64 0)
ret i64 %call
}
-; CHECK-LABEL: noDebug
+; CHECK-LABEL: fn1NoDebug
; CHECK: popq %rcx
-; CHECK: ret
-
+; CHECK-NEXT: ret
-define i64 @withDebug(i64 %a) !dbg !4 {
+define i64 @fn1WithDebug(i64 %a) !dbg !4 {
%call = call i64 @fn(i64 %a, i64 0)
tail call void @llvm.dbg.value(metadata i64 %call, i64 0, metadata !5, metadata !6), !dbg !7
ret i64 %call
}
-; CHECK-LABEL: withDebug
+; CHECK-LABEL: fn1WithDebug
; CHECK: popq %rcx
-; CHECK: ret
+; CHECK-NEXT: ret
+
+%struct.Buffer = type { i8, [63 x i8] }
+
+define void @fn2NoDebug(%struct.Buffer* byval align 64 %p1) {
+ ret void
+}
+
+; CHECK-LABEL: fn2NoDebug
+; CHECK: and
+; CHECK-NOT: add
+; CHECK-NOT: sub
+; CHECK: mov
+; CHECK-NEXT: pop
+; CHECK-NEXT: ret
+
+define void @fn2WithDebug(%struct.Buffer* byval align 64 %p1) !dbg !4 {
+ call void @llvm.dbg.declare(metadata %struct.Buffer* %p1, metadata !5, metadata !6), !dbg !7
+ ret void
+}
+; CHECK-LABEL: fn2WithDebug
+; CHECK: and
+; CHECK-NOT: add
+; CHECK-NOT: sub
+; CHECK: mov
+; CHECK-NEXT: pop
+; CHECK-NEXT: ret
declare i64 @fn(i64, i64)
declare void @llvm.dbg.value(metadata, i64, metadata, metadata)
+declare void @llvm.dbg.declare(metadata, metadata, metadata)
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!2,!3}
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