forked from OSchip/llvm-project
4121bce3f6
Arm code has two instruction encodings "thumb" and "arm". When branching from one code encoding to another, you need to use an instruction that switches the instruction mode. Usually the transition only happens at call sites, and the linker can transform a BL instruction in BLX (or vice versa). But if the compiler did a tail call optimization and a function ends with a branch (not branch and link), there is no pc-rel BX instruction. The ShimPass looks for pc-rel B instructions that will need to switch mode. For those cases it synthesizes a shim which does the transition, then modifies the original atom with the B instruction to target to the shim atom. llvm-svn: 219655 |
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| Core | ||
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| Passes | ||
| ReaderWriter | ||
| CMakeLists.txt | ||
| Makefile | ||