Module: Mesa Branch: master Commit: 9c3be6d21fa6a45852045d0286b80fb420f82fe3 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=9c3be6d21fa6a45852045d0286b80fb420f82fe3
Author: Ben Crocker <[email protected]> Date: Wed Nov 13 20:27:24 2019 +0000 llvmpipe: use ppc64le/ppc64 Large code model for JIT-compiled shaders Large programs, e.g. gnome-shell and firefox, may tax the addressability of the Medium code model once a (potentially unbounded) number of dynamically generated JIT-compiled shader programs are linked in and relocated. Yet the default code model as of LLVM 8 is Medium or even Small. The cost of changing from Medium to Large is negligible: - an additional 8-byte pointer stored immediately before the shader entrypoint; - change an add-immediate (addis) instruction to a load (ld). Testing with WebGL Conformance (https://www.khronos.org/registry/webgl/sdk/tests/webgl-conformance-tests.html) yields clean runs with this change (and crashes without it). Testing with glxgears shows no detectable performance difference. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1753327, 1753789, 1543572, 1747110, and 1582226 Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/223 Co-authored by: Nemanja Ivanovic <[email protected]>, Tom Stellard <[email protected]> CC: [email protected] Signed-off-by: Ben Crocker <[email protected]> --- src/gallium/auxiliary/gallivm/lp_bld_misc.cpp | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp index e80676d5062..40cc96824f3 100644 --- a/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp +++ b/src/gallium/auxiliary/gallivm/lp_bld_misc.cpp @@ -456,7 +456,20 @@ lp_build_create_jit_compiler_for_module(LLVMExecutionEngineRef *OutJIT, * when not using MCJIT so no instructions are generated which the old JIT * can't handle. Not entirely sure if we really need to do anything yet. */ -#if UTIL_ARCH_LITTLE_ENDIAN && defined(PIPE_ARCH_PPC_64) + +#ifdef PIPE_ARCH_PPC_64 + /* + * Large programs, e.g. gnome-shell and firefox, may tax the addressability + * of the Medium code model once dynamically generated JIT-compiled shader + * programs are linked in and relocated. Yet the default code model as of + * LLVM 8 is Medium or even Small. + * The cost of changing from Medium to Large is negligible: + * - an additional 8-byte pointer stored immediately before the shader entrypoint; + * - change an add-immediate (addis) instruction to a load (ld). + */ + builder.setCodeModel(CodeModel::Large); + +#if UTIL_ARCH_LITTLE_ENDIAN /* * Versions of LLVM prior to 4.0 lacked a table entry for "POWER8NVL", * resulting in (big-endian) "generic" being returned on @@ -469,6 +482,7 @@ lp_build_create_jit_compiler_for_module(LLVMExecutionEngineRef *OutJIT, if (MCPU == "generic") MCPU = "pwr8"; #endif +#endif builder.setMCPU(MCPU); if (gallivm_debug & (GALLIVM_DEBUG_IR | GALLIVM_DEBUG_ASM | GALLIVM_DEBUG_DUMP_BC)) { debug_printf("llc -mcpu option: %s\n", MCPU.str().c_str()); _______________________________________________ mesa-commit mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/mesa-commit
