Add a pass to lower is.constant and objectsize intrinsics

This pass lowers is.constant and objectsize intrinsics not simplified by
earlier constant folding, i.e. if the object given is not constant or if
not using the optimized pass chain. The result is recursively simplified
and constant conditionals are pruned, so that dead blocks are removed
even for -O0. This allows inline asm blocks with operand constraints to
work all the time.

The new pass replaces the existing lowering in the codegen-prepare pass
and fallbacks in SDAG/GlobalISEL and FastISel. The latter now assert
on the intrinsics.

Differential Revision: https://reviews.llvm.org/D65280

llvm-svn: 374743

1 files changed, 3 insertions, 0 deletions

diff --git a/llvm/include/llvm-c/Transforms/Scalar.h b/llvm/include/llvm-c/Transforms/Scalar.h
index 484ac90ab5d..6f3a3d8b375 100644
--- a/llvm/include/llvm-c/Transforms/Scalar.h
+++ b/llvm/include/llvm-c/Transforms/Scalar.h
@@ -147,6 +147,9 @@ void LLVMAddEarlyCSEMemSSAPass(LLVMPassManagerRef PM);
 /** See llvm::createLowerExpectIntrinsicPass function */
 void LLVMAddLowerExpectIntrinsicPass(LLVMPassManagerRef PM);
 
+/** See llvm::createLowerConstantIntrinsicsPass function */
+void LLVMAddLowerConstantIntrinsicsPass(LLVMPassManagerRef PM);
+
 /** See llvm::createTypeBasedAliasAnalysisPass function */
 void LLVMAddTypeBasedAliasAnalysisPass(LLVMPassManagerRef PM);