Re: [GHC] #11138: Kill the terrible LLVM Mangler

#11138: Kill the terrible LLVM Mangler -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: task | Status: new Priority: normal | Milestone: Component: Compiler (LLVM) | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Other | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by angerman): * cc: gmainland (added) Comment: This was added already in 2013. afdb2fc3d2013ced6c136853f4e24e84b6f150e9 \\ Author: Geoffrey Mainland \\ AuthorDate: Thu Feb 14 21:25:54 2013 +0000 \\ Commit: Geoffrey Mainland \\ CommitDate: Sun Sep 22 22:33:59 2013 -0400 **Set LLVM option -stack-alignment=32 when compiling AVX instructions.** ---- Then mangler code however was created earlier in 2011. f8c51678b0e60aad8ee1e4c57af746fa792a3546\\ Author: Geoffrey Mainland \\ AuthorDate: Sat Nov 26 12:45:23 2011 +0000\\ Commit: Geoffrey Mainland \\ CommitDate: Sun Sep 22 22:33:59 2013 -0400 **Fixup stack spills when generating AVX instructions.** LLVM uses aligned AVX moves to spill values onto the stack, which requires 32-bye aligned stacks. Since the stack in only 16-byte aligned, LLVM inserts extra instructions that munge the stack pointer. This is very very bad for the GHC calling convention, so we tell LLVM to assume the stack is 32-byte aligned. This patch rewrites the spill instructions that LLVM generates so they do not require an aligned stack. ---- Could it be that the Mangler code is some ancient relict? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11138#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler