GlobalISel: Add known bits to InstructionSelector

AMDGPU uses this for some addressing mode selection patterns. The
analysis run itself doesn't do anything so it seems easier to just
always require this than adding a way to opt in.

llvm-svn: 370388

5 files changed, 16 insertions, 4 deletions

diff --git a/llvm/include/llvm/CodeGen/GlobalISel/InstructionSelector.h b/llvm/include/llvm/CodeGen/GlobalISel/InstructionSelector.h
index 62010238d24..e4877b7ad63 100644
--- a/llvm/include/llvm/CodeGen/GlobalISel/InstructionSelector.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/InstructionSelector.h
@@ -31,6 +31,7 @@ namespace llvm {
 
 class APInt;
 class APFloat;
+class GISelKnownBits;
 class MachineInstr;
 class MachineInstrBuilder;
 class MachineFunction;
@@ -381,11 +382,15 @@ public:
   virtual bool select(MachineInstr &I) = 0;
 
   CodeGenCoverage *CoverageInfo = nullptr;
+  GISelKnownBits *KnownBits = nullptr;
   MachineFunction *MF = nullptr;
 
   /// Setup per-MF selector state.
-  virtual void setupMF(MachineFunction &mf, CodeGenCoverage &covinfo) {
+  virtual void setupMF(MachineFunction &mf,
+                       GISelKnownBits &KB,
+                       CodeGenCoverage &covinfo) {
     CoverageInfo = &covinfo;
+    KnownBits = &KB;
     MF = &mf;
   }
 
diff --git a/llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp b/llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp
index d699b4d2d42..1fc12359cd8 100644
--- a/llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp
@@ -12,6 +12,7 @@
 #include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
 #include "llvm/ADT/PostOrderIterator.h"
 #include "llvm/ADT/Twine.h"
+#include "llvm/CodeGen/GlobalISel/GISelKnownBits.h"
 #include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
 #include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
 #include "llvm/CodeGen/GlobalISel/Utils.h"
@@ -53,6 +54,8 @@ InstructionSelect::InstructionSelect() : MachineFunctionPass(ID) { }
 
 void InstructionSelect::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<TargetPassConfig>();
+  AU.addRequired<GISelKnownBitsAnalysis>();
+  AU.addPreserved<GISelKnownBitsAnalysis>();
   getSelectionDAGFallbackAnalysisUsage(AU);
   MachineFunctionPass::getAnalysisUsage(AU);
 }
@@ -64,12 +67,13 @@ bool InstructionSelect::runOnMachineFunction(MachineFunction &MF) {
     return false;
 
   LLVM_DEBUG(dbgs() << "Selecting function: " << MF.getName() << '\n');
+  GISelKnownBits &KB = getAnalysis<GISelKnownBitsAnalysis>().get(MF);
 
   const TargetPassConfig &TPC = getAnalysis<TargetPassConfig>();
   InstructionSelector *ISel = MF.getSubtarget().getInstructionSelector();
   CodeGenCoverage CoverageInfo;
   assert(ISel && "Cannot work without InstructionSelector");
-  ISel->setupMF(MF, CoverageInfo);
+  ISel->setupMF(MF, KB, CoverageInfo);
 
   // An optimization remark emitter. Used to report failures.
   MachineOptimizationRemarkEmitter MORE(MF, /*MBFI=*/nullptr);
diff --git a/llvm/lib/Target/AArch64/AArch64InstructionSelector.cpp b/llvm/lib/Target/AArch64/AArch64InstructionSelector.cpp
index dda8f1c0968..1865e577b21 100644
--- a/llvm/lib/Target/AArch64/AArch64InstructionSelector.cpp
+++ b/llvm/lib/Target/AArch64/AArch64InstructionSelector.cpp
@@ -54,8 +54,9 @@ public:
   bool select(MachineInstr &I) override;
   static const char *getName() { return DEBUG_TYPE; }
 
-  void setupMF(MachineFunction &MF, CodeGenCoverage &CoverageInfo) override {
-    InstructionSelector::setupMF(MF, CoverageInfo);
+  void setupMF(MachineFunction &MF, GISelKnownBits &KB,
+               CodeGenCoverage &CoverageInfo) override {
+    InstructionSelector::setupMF(MF, KB, CoverageInfo);
 
     // hasFnAttribute() is expensive to call on every BRCOND selection, so
     // cache it here for each run of the selector.
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/gisel-commandline-option.ll b/llvm/test/CodeGen/AArch64/GlobalISel/gisel-commandline-option.ll
index 6d628ed5a29..fd7809fa0c1 100644
--- a/llvm/test/CodeGen/AArch64/GlobalISel/gisel-commandline-option.ll
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/gisel-commandline-option.ll
@@ -53,6 +53,7 @@
 ; VERIFY-NEXT:   Verify generated machine code
 ; ENABLED-O0-NEXT:  Localizer
 ; VERIFY-O0-NEXT:   Verify generated machine code
+; ENABLED-NEXT: Analysis for ComputingKnownBits
 ; ENABLED-NEXT:  InstructionSelect
 ; VERIFY-NEXT:   Verify generated machine code
 ; ENABLED-NEXT:  ResetMachineFunction
diff --git a/llvm/test/CodeGen/AArch64/O0-pipeline.ll b/llvm/test/CodeGen/AArch64/O0-pipeline.ll
index 38af1810feb..9611946f710 100644
--- a/llvm/test/CodeGen/AArch64/O0-pipeline.ll
+++ b/llvm/test/CodeGen/AArch64/O0-pipeline.ll
@@ -41,6 +41,7 @@
 ; CHECK-NEXT:       Legalizer
 ; CHECK-NEXT:       RegBankSelect
 ; CHECK-NEXT:       Localizer
+; CHECK-NEXT:       Analysis for ComputingKnownBits
 ; CHECK-NEXT:       InstructionSelect
 ; CHECK-NEXT:       ResetMachineFunction
 ; CHECK-NEXT:       AArch64 Instruction Selection