[BlockExtractor] Extend the file format to support the grouping of basic blocks
Prior to this patch, each basic block listed in the extrack-blocks-file
would be extracted to a different function.
This patch adds the support for comma separated list of basic blocks
to form group.
When the region formed by a group is not extractable, e.g., not single
entry, all the blocks of that group are left untouched.
Let us see this new format in action (comments are not part of the
file format):
;; funcName bbName[,bbName...]
foo bb1 ;; Extract bb1 in its own function
foo bb2,bb3 ;; Extract bb2,bb3 in their own function
bar bb1,bb4 ;; Extract bb1,bb4 in their own function
bar bb2 ;; Extract bb2 in its own function
Assuming all regions are extractable, this will create one function and
thus one call per region.
Differential Revision: https://reviews.llvm.org/D60746
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358701 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/IPO/BlockExtractor.cpp b/lib/Transforms/IPO/BlockExtractor.cpp
index eb12d03..31c09eb 100644
--- a/lib/Transforms/IPO/BlockExtractor.cpp
+++ b/lib/Transforms/IPO/BlockExtractor.cpp
@@ -22,6 +22,7 @@
#include "llvm/Transforms/IPO.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/CodeExtractor.h"
+
using namespace llvm;
#define DEBUG_TYPE "block-extractor"
@@ -35,19 +36,25 @@
cl::opt<bool> BlockExtractorEraseFuncs("extract-blocks-erase-funcs",
cl::desc("Erase the existing functions"),
cl::Hidden);
-
namespace {
class BlockExtractor : public ModulePass {
- SmallVector<BasicBlock *, 16> Blocks;
+ SmallVector<SmallVector<BasicBlock *, 16>, 4> GroupsOfBlocks;
bool EraseFunctions;
- SmallVector<std::pair<std::string, std::string>, 32> BlocksByName;
+ /// Map a function name to groups of blocks.
+ SmallVector<std::pair<std::string, SmallVector<std::string, 4>>, 4>
+ BlocksByName;
public:
static char ID;
BlockExtractor(const SmallVectorImpl<BasicBlock *> &BlocksToExtract,
bool EraseFunctions)
- : ModulePass(ID), Blocks(BlocksToExtract.begin(), BlocksToExtract.end()),
- EraseFunctions(EraseFunctions) {
+ : ModulePass(ID), EraseFunctions(EraseFunctions) {
+ // We want one group per element of the input list.
+ for (BasicBlock *BB : BlocksToExtract) {
+ SmallVector<BasicBlock *, 16> NewGroup;
+ NewGroup.push_back(BB);
+ GroupsOfBlocks.push_back(NewGroup);
+ }
if (!BlockExtractorFile.empty())
loadFile();
}
@@ -81,8 +88,17 @@
Buf->getBuffer().split(Lines, '\n', /*MaxSplit=*/-1,
/*KeepEmpty=*/false);
for (const auto &Line : Lines) {
- auto FBPair = Line.split(' ');
- BlocksByName.push_back({FBPair.first, FBPair.second});
+ SmallVector<StringRef, 4> LineSplit;
+ Line.split(LineSplit, ' ', /*MaxSplit=*/-1,
+ /*KeepEmpty=*/false);
+ if (LineSplit.empty())
+ continue;
+ SmallVector<StringRef, 4> BBNames;
+ LineSplit[1].split(BBNames, ',', /*MaxSplit=*/-1,
+ /*KeepEmpty=*/false);
+ if (BBNames.empty())
+ report_fatal_error("Missing bbs name");
+ BlocksByName.push_back({LineSplit[0], {BBNames.begin(), BBNames.end()}});
}
}
@@ -129,33 +145,46 @@
}
// Get all the blocks specified in the input file.
+ unsigned NextGroupIdx = GroupsOfBlocks.size();
+ GroupsOfBlocks.resize(NextGroupIdx + BlocksByName.size());
for (const auto &BInfo : BlocksByName) {
Function *F = M.getFunction(BInfo.first);
if (!F)
report_fatal_error("Invalid function name specified in the input file");
- auto Res = llvm::find_if(*F, [&](const BasicBlock &BB) {
- return BB.getName().equals(BInfo.second);
- });
- if (Res == F->end())
- report_fatal_error("Invalid block name specified in the input file");
- Blocks.push_back(&*Res);
+ for (const auto &BBInfo : BInfo.second) {
+ auto Res = llvm::find_if(*F, [&](const BasicBlock &BB) {
+ return BB.getName().equals(BBInfo);
+ });
+ if (Res == F->end())
+ report_fatal_error("Invalid block name specified in the input file");
+ GroupsOfBlocks[NextGroupIdx].push_back(&*Res);
+ }
+ ++NextGroupIdx;
}
- // Extract basic blocks.
- for (BasicBlock *BB : Blocks) {
- // Check if the module contains BB.
- if (BB->getParent()->getParent() != &M)
- report_fatal_error("Invalid basic block");
- LLVM_DEBUG(dbgs() << "BlockExtractor: Extracting "
- << BB->getParent()->getName() << ":" << BB->getName()
- << "\n");
- SmallVector<BasicBlock *, 2> BlocksToExtractVec;
- BlocksToExtractVec.push_back(BB);
- if (const InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
- BlocksToExtractVec.push_back(II->getUnwindDest());
- CodeExtractor(BlocksToExtractVec).extractCodeRegion();
- ++NumExtracted;
- Changed = true;
+ // Extract each group of basic blocks.
+ for (auto &BBs : GroupsOfBlocks) {
+ SmallVector<BasicBlock *, 32> BlocksToExtractVec;
+ for (BasicBlock *BB : BBs) {
+ // Check if the module contains BB.
+ if (BB->getParent()->getParent() != &M)
+ report_fatal_error("Invalid basic block");
+ LLVM_DEBUG(dbgs() << "BlockExtractor: Extracting "
+ << BB->getParent()->getName() << ":" << BB->getName()
+ << "\n");
+ BlocksToExtractVec.push_back(BB);
+ if (const InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
+ BlocksToExtractVec.push_back(II->getUnwindDest());
+ ++NumExtracted;
+ Changed = true;
+ }
+ Function *F = CodeExtractor(BlocksToExtractVec).extractCodeRegion();
+ if (F)
+ LLVM_DEBUG(dbgs() << "Extracted group '" << (*BBs.begin())->getName()
+ << "' in: " << F->getName() << '\n');
+ else
+ LLVM_DEBUG(dbgs() << "Failed to extract for group '"
+ << (*BBs.begin())->getName() << "'\n");
}
// Erase the functions.
diff --git a/test/Transforms/BlockExtractor/extract-blocks-with-groups.ll b/test/Transforms/BlockExtractor/extract-blocks-with-groups.ll
new file mode 100644
index 0000000..0c5b173
--- /dev/null
+++ b/test/Transforms/BlockExtractor/extract-blocks-with-groups.ll
@@ -0,0 +1,122 @@
+; Extract the 'if', 'then', and 'else' blocks into the same function.
+; RUN: echo 'foo if,then,else' > %t
+; Make sure we can still extract a single basic block
+; RUN: echo 'foo end' >> %t
+; RUN: echo 'bar bb14,bb20' >> %t
+; RUN: opt -S -extract-blocks -extract-blocks-file=%t %s | FileCheck %s
+
+; CHECK-LABEL: foo
+;
+; CHECK: if:
+; The diamond will produce an i32 value, make sure we account for that.
+; CHECK: [[RES_VAL_ADDR:%[^ ]*]] = alloca i32
+; CHECK-NEXT: br label %[[FOO_DIAMOND_LABEL:.*$]]
+;
+; The if-then-else blocks should be in just one function.
+; CHECK: [[FOO_DIAMOND_LABEL]]:
+; CHECK: call void [[FOO_DIAMOND:@[^(]*]](i32 %arg1, i32 %arg, i32* [[RES_VAL_ADDR]])
+; CHECK-NEXT: [[RES_VAL:%[^ ]*]] = load i32, i32* [[RES_VAL_ADDR]]
+; Then it should directly jump to end.
+; CHECK: br label %[[FOO_END_LABEL:.*$]]
+;
+; End should have been extracted into its own function.
+; CHECK: [[FOO_END_LABEL]]:
+; CHECK: [[CMP:%[^ ]*]] = call i1 [[FOO_END:@[^(]*]](i32 [[RES_VAL]], i32 %arg)
+; CHECK-NEXT: br i1 [[CMP]], label %ret0, label %ret1
+define i32 @foo(i32 %arg, i32 %arg1) {
+if:
+ %tmp5 = icmp sgt i32 %arg, 0
+ %tmp8 = icmp sgt i32 %arg1, 0
+ %or.cond = and i1 %tmp5, %tmp8
+ br i1 %or.cond, label %then, label %else
+
+then:
+ %tmp12 = shl i32 %arg1, 2
+ %tmp13 = add nsw i32 %tmp12, %arg
+ br label %end
+
+else:
+ %tmp22 = mul nsw i32 %arg, 3
+ %tmp24 = sdiv i32 %arg1, 6
+ %tmp25 = add nsw i32 %tmp24, %tmp22
+ br label %end
+
+end:
+ %tmp.0 = phi i32 [ %tmp13, %then ], [ %tmp25, %else ]
+ %and0 = and i32 %tmp.0, %arg
+ %cmp1 = icmp slt i32 %and0, 0
+ br i1 %cmp1, label %ret0, label %ret1
+
+ret0:
+ ret i32 0
+
+ret1:
+ ret i32 1
+}
+
+; CHECK-LABEL: bar
+;
+; Check that we extracted bb14 and bb20 in their own (shared) function.
+; CHECK: bb
+; CHECK: br i1 %or.cond, label %bb9, label %[[BAR_DIAMOND_LABEL:.*$]]
+;
+; CHECK: [[BAR_DIAMOND_LABEL]]:
+; CHECK: [[CMP:%[^ ]*]] = call i1 [[BAR_DIAMOND:@[^(]*]](i32 %arg1, i32 %arg, i32*
+; CHECK: br i1 [[CMP]], label %bb26, label %bb30
+define i32 @bar(i32 %arg, i32 %arg1) {
+bb:
+ %tmp5 = icmp sgt i32 %arg, 0
+ %tmp8 = icmp sgt i32 %arg1, 0
+ %or.cond = and i1 %tmp5, %tmp8
+ br i1 %or.cond, label %bb9, label %bb14
+
+bb9: ; preds = %bb
+ %tmp12 = shl i32 %arg1, 2
+ %tmp13 = add nsw i32 %tmp12, %arg
+ br label %bb30
+
+bb14: ; preds = %bb
+ %0 = and i32 %arg1, %arg
+ %1 = icmp slt i32 %0, 0
+ br i1 %1, label %bb20, label %bb26
+
+bb20: ; preds = %bb14
+ %tmp22 = mul nsw i32 %arg, 3
+ %tmp24 = sdiv i32 %arg1, 6
+ %tmp25 = add nsw i32 %tmp24, %tmp22
+ br label %bb30
+
+bb26: ; preds = %bb14
+ %tmp29 = sub nsw i32 %arg, %arg1
+ br label %bb30
+
+bb30: ; preds = %bb26, %bb20, %bb9
+ %tmp.0 = phi i32 [ %tmp13, %bb9 ], [ %tmp25, %bb20 ], [ %tmp29, %bb26 ]
+ ret i32 %tmp.0
+}
+
+; Check that we extracted the three asked basic blocks.
+; CHECK: [[FOO_DIAMOND]]
+; CHECK: then:
+; Make sure the function doesn't end in the middle of the
+; list of the blocks we are checking.
+; CHECK-NOT: }
+; CHECK: else:
+; CHECK-NOT: }
+; The name of the if block is weird because it had to be split
+; since it was the name of the entry of the original function.
+; CHECK: if.split:
+; CHECK: }
+
+; CHECK: [[FOO_END]]
+; CHECK-NOT: }
+; CHECK: end:
+; CHECK: }
+
+; Check that we extracted the two asked basic blocks.
+; CHECK: [[BAR_DIAMOND]]
+; CHECK-NOT: }
+; CHECK: bb14:
+; CHECK-NOT: }
+; CHECK: bb20:
+; CHECK: }
