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[CodeGenPrepare] Use MapVector to stabilize iteration order

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DenseMap iteration order is not guaranteed to be deterministic.

Without the change,
llvm/test/Transforms/CodeGenPrepare/X86/statepoint-relocate.ll would
fail when `combineHashValue` changes (#95970).

Fixes: dba7329ebb
This commit is contained in:
Fangrui Song
2024-06-18 17:19:50 -07:00
parent 139f896c0f
commit 8ea31db272
2 changed files with 6 additions and 4 deletions
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6
llvm/lib/CodeGen/CodeGenPrepare.cpp
View File

@@ -1194,12 +1194,12 @@ void CodeGenPrepare::eliminateMostlyEmptyBlock(BasicBlock *BB) {
// derived pointer relocation instructions given a vector of all relocate calls
static void computeBaseDerivedRelocateMap(
const SmallVectorImpl<GCRelocateInst *> &AllRelocateCalls,
DenseMap<GCRelocateInst *, SmallVector<GCRelocateInst *, 2>>
MapVector<GCRelocateInst *, SmallVector<GCRelocateInst *, 0>>
&RelocateInstMap) {
// Collect information in two maps: one primarily for locating the base object
// while filling the second map; the second map is the final structure holding
// a mapping between Base and corresponding Derived relocate calls
DenseMap<std::pair<unsigned, unsigned>, GCRelocateInst *> RelocateIdxMap;
MapVector<std::pair<unsigned, unsigned>, GCRelocateInst *> RelocateIdxMap;
for (auto *ThisRelocate : AllRelocateCalls) {
auto K = std::make_pair(ThisRelocate->getBasePtrIndex(),
ThisRelocate->getDerivedPtrIndex());
@@ -1375,7 +1375,7 @@ bool CodeGenPrepare::simplifyOffsetableRelocate(GCStatepointInst &I) {
// RelocateInstMap is a mapping from the base relocate instruction to the
// corresponding derived relocate instructions
DenseMap<GCRelocateInst *, SmallVector<GCRelocateInst *, 2>> RelocateInstMap;
MapVector<GCRelocateInst *, SmallVector<GCRelocateInst *, 0>> RelocateInstMap;
computeBaseDerivedRelocateMap(AllRelocateCalls, RelocateInstMap);
if (RelocateInstMap.empty())
return false;

4
llvm/test/Transforms/CodeGenPrepare/X86/statepoint-relocate.ll
View File

@@ -18,10 +18,11 @@ entry:
}
define i32 @test_sor_two_derived(ptr addrspace(1) %base) gc "statepoint-example" {
; CHECK-LABEL: @test_sor_two_derived(
; CHECK: getelementptr i32, ptr addrspace(1) %base, i32 15
; CHECK: getelementptr i32, ptr addrspace(1) %base, i32 12
; CHECK: getelementptr i32, ptr addrspace(1) %base-new, i32 12
; CHECK: getelementptr i32, ptr addrspace(1) %base-new, i32 15
; CHECK: getelementptr i32, ptr addrspace(1) %base-new, i32 12
entry:
%ptr = getelementptr i32, ptr addrspace(1) %base, i32 15
%ptr2 = getelementptr i32, ptr addrspace(1) %base, i32 12
@@ -34,6 +35,7 @@ entry:
}
define i32 @test_sor_ooo(ptr addrspace(1) %base) gc "statepoint-example" {
; CHECK-LABEL: @test_sor_ooo(
; CHECK: getelementptr i32, ptr addrspace(1) %base, i32 15
; CHECK: getelementptr i32, ptr addrspace(1) %base-new, i32 15
entry: