[llvm-commits] [llvm-gcc-4.2] r45628 - /llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp

[Duncan Sands]

Author: baldrick
Date: Sat Jan  5 11:48:09 2008
New Revision: 45628

URL: http://llvm.org/viewvc/llvm-project?rev=45628&view=rev
Log:
The Ada front-end only sets flag_exceptions after
processing the file (but before gimplification).
At system init time flag_exceptions is thus never
set, which means that --enable-eh will never be
passed to the code generators.  Make it possible
to specify options like flag_exceptions late in
the day.  This requires setting up optimization
passes late too, since otherwise a LowerInvoke
pass will be scheduled because ExceptionHandling
is not set.

Modified:
    llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp

Modified: llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp?rev=45628&r1=45627&r2=45628&view=diff

==============================================================================
--- llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp (original)
+++ llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp Sat Jan  5 11:48:09 2008
@@ -43,6 +43,7 @@
 #include "llvm/Target/TargetLowering.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetMachineRegistry.h"
+#include "llvm/Target/TargetOptions.h"
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/Transforms/IPO.h"
 #include "llvm/ADT/StringExtras.h"
@@ -97,6 +98,8 @@
 static FunctionPassManager *CodeGenPasses = 0;
 
 static void createOptimizationPasses();
+bool OptimizationPassesCreated = false;
+static void destroyOptimizationPasses();
 
 void llvm_initialize_backend(void) {
   // Initialize LLVM options.
@@ -123,8 +126,6 @@
     Args.push_back("--debug-pass=Structure");
   if (flag_debug_pass_arguments)
     Args.push_back("--debug-pass=Arguments");
-  if (flag_exceptions)
-    Args.push_back("--enable-eh");
 
   // If there are options that should be passed through to the LLVM backend
   // directly from the command line, do so now.  This is mainly for debugging
@@ -197,6 +198,12 @@
     TheDebugInfo = new DebugInfo(TheModule);
 }
 
+/// Set backend options that may only be known at codegen time.
+void performLateBackendInitialization(void) {
+  // The Ada front-end sets flag_exceptions only after processing the file.
+  ExceptionHandling = flag_exceptions;
+}
+
 void llvm_lang_dependent_init(const char *Name) {
   if (Name)
     TheModule->setModuleIdentifier(Name);
@@ -227,18 +234,14 @@
     exit(1);
   }
 
-  if (PerFunctionPasses || PerModulePasses || CodeGenPasses) {
-    delete PerFunctionPasses;
-    delete PerModulePasses;
-    delete CodeGenPasses;
+  if (OptimizationPassesCreated) {
+    destroyOptimizationPasses();
 
     // Don't run codegen, when we should output PCH
-    if (!flag_pch_file)
-      createOptimizationPasses();
-    else
+    if (flag_pch_file)
       llvm_pch_write_init();
   }
-    
+
   // Read LLVM Types string table
   readLLVMTypesStringTable();
   readLLVMValues();
@@ -255,6 +258,8 @@
   AsmOutStream = new oFILEstream(asm_out_file);
   AsmOutFile = new OStream(*AsmOutStream);
 
+  assert(!OptimizationPassesCreated);
+  OptimizationPassesCreated = true;
   PerModulePasses = new PassManager();
   PerModulePasses->add(new TargetData(*TheTarget->getTargetData()));
 
@@ -271,7 +276,28 @@
   timevar_pop(TV_LLVM_INIT);
 }
 
+static void destroyOptimizationPasses() {
+  assert(OptimizationPassesCreated ||
+         (!PerFunctionPasses && !PerModulePasses && !CodeGenPasses));
+
+  delete PerFunctionPasses;
+  delete PerModulePasses;
+  delete CodeGenPasses;
+
+  PerFunctionPasses = 0;
+  PerModulePasses   = 0;
+  CodeGenPasses     = 0;
+  OptimizationPassesCreated = false;
+}
+
 static void createOptimizationPasses() {
+  assert(OptimizationPassesCreated ||
+         (!PerFunctionPasses && !PerModulePasses && !CodeGenPasses));
+
+  if (OptimizationPassesCreated)
+    return;
+  OptimizationPassesCreated = true;
+
   // Create and set up the per-function pass manager.
   // FIXME: Move the code generator to be function-at-a-time.
   PerFunctionPasses =
@@ -368,19 +394,11 @@
     // Emit an LLVM .bc file to the output.  This is used when passed
     // -emit-llvm -c to the GCC driver.
     PerModulePasses->add(CreateBitcodeWriterPass(*AsmOutStream));
-
-    // Disable emission of .ident into the output file... which is completely
-    // wrong for llvm/.bc emission cases.
-    flag_no_ident = 1;
     HasPerModulePasses = true;
   } else if (emit_llvm) {
     // Emit an LLVM .ll file to the output.  This is used when passed 
     // -emit-llvm -S to the GCC driver.
     PerModulePasses->add(new PrintModulePass(AsmOutFile));
-    
-    // Disable emission of .ident into the output file... which is completely
-    // wrong for llvm/.bc emission cases.
-    flag_no_ident = 1;
     HasPerModulePasses = true;
   } else {
     FunctionPassManager *PM;
@@ -436,11 +454,14 @@
   timevar_push(TV_LLVM_INIT);
   AsmOutStream = new oFILEstream(asm_out_file);
   AsmOutFile = new OStream(*AsmOutStream);
-  
+
   flag_llvm_pch_read = 0;
 
-  createOptimizationPasses();
-  
+  if (emit_llvm_bc || emit_llvm)
+    // Disable emission of .ident into the output file... which is completely
+    // wrong for llvm/.bc emission cases.
+    flag_no_ident = 1;
+
   AttributeUsedGlobals.clear();
   timevar_pop(TV_LLVM_INIT);
 }
@@ -469,6 +490,9 @@
   timevar_push(TV_LLVM_PERFILE);
   llvm_shutdown_obj X;  // Call llvm_shutdown() on exit.
 
+  performLateBackendInitialization();
+  createOptimizationPasses();
+
   if (flag_pch_file) {
     writeLLVMTypesStringTable();
     writeLLVMValues();
@@ -582,7 +606,10 @@
     Fn->dump();
   }
 #endif
-  
+
+  performLateBackendInitialization();
+  createOptimizationPasses();
+
   if (PerFunctionPasses)
     PerFunctionPasses->run(*Fn);