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Adding check for OS AVX support to auto-dispatch code

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This commit is contained in:
Dmitry Babokin
2013-09-18 14:24:46 +04:00
parent 971d5f8d12
commit 43245bbc11
1 changed files with 49 additions and 32 deletions
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81
builtins/dispatch.ll
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@@ -1,4 +1,4 @@
;; Copyright (c) 2011, Intel Corporation
;; Copyright (c) 2011-2013, Intel Corporation
;; All rights reserved.
;;
;; Redistribution and use in source and binary forms, with or without
@@ -41,15 +41,13 @@
@__system_best_isa = internal global i32 -1
declare void @abort() noreturn
;; The below is the result of running "clang -O2 -emit-llvm -c -o -" on the
;; following code... Specifically, __get_system_isa should return a value
;; corresponding to one of the Target::ISA enumerant values that gives the
;; most capable ISA that the curremt system can run.
;;
;; Note: clang from LLVM 3.0 should be used if this is updated, for maximum
;; backwards compatibility for anyone building ispc with LLVM 3.0
;; Note: clang from LLVM 3.1 should be used if this is updated, for maximum
;; backwards compatibility for anyone building ispc with LLVM 3.1
;;
;; #include <stdint.h>
;; #include <stdlib.h>
@@ -60,7 +58,7 @@ declare void @abort() noreturn
;; : "0" (infoType));
;; }
;;
;; /* Save %ebx in case it's the PIC register */
;; // Save %ebx in case it's the PIC register.
;; static void __cpuid_count(int info[4], int level, int count) {
;; __asm__ __volatile__ ("xchg{l}\t{%%}ebx, %1\n\t"
;; "cpuid\n\t"
@@ -69,13 +67,23 @@ declare void @abort() noreturn
;; : "0" (level), "2" (count));
;; }
;;
;; static int __os_has_avx_support() {
;; // Check xgetbv; this uses a .byte sequence instead of the instruction
;; // directly because older assemblers do not include support for xgetbv and
;; // there is no easy way to conditionally compile based on the assembler used.
;; int rEAX, rEDX;
;; __asm__ __volatile__ (".byte 0x0f, 0x01, 0xd0" : "=a" (rEAX), "=d" (rEDX) : "c" (0));
;; return (rEAX & 6) == 6;
;; }
;;
;; int32_t __get_system_isa() {
;; int info[4];
;; __cpuid(info, 1);
;;
;; /* NOTE: the values returned below must be the same as the
;; corresponding enumerant values in Target::ISA. */
;; if ((info[2] & (1 << 28)) != 0) {
;; // NOTE: the values returned below must be the same as the
;; // corresponding enumerant values in Target::ISA.
;; if ((info[2] & (1 << 28)) != 0 &&
;; __os_has_avx_support()) {
;; if ((info[2] & (1 << 29)) != 0 && // F16C
;; (info[2] & (1 << 30)) != 0) { // RDRAND
;; // So far, so good. AVX2?
@@ -98,47 +106,56 @@ declare void @abort() noreturn
;; abort();
;; }
define i32 @__get_system_isa() nounwind uwtable ssp {
define i32 @__get_system_isa() nounwind uwtable {
entry:
%0 = tail call { i32, i32, i32, i32 } asm sideeffect "cpuid", "={ax},={bx},={cx},={dx},0,~{dirflag},~{fpsr},~{flags}"(i32 1) nounwind
%asmresult5.i = extractvalue { i32, i32, i32, i32 } %0, 2
%asmresult6.i = extractvalue { i32, i32, i32, i32 } %0, 3
%and = and i32 %asmresult5.i, 268435456
%cmp = icmp eq i32 %and, 0
br i1 %cmp, label %if.else13, label %if.then
br i1 %cmp, label %if.else14, label %land.lhs.true
if.then: ; preds = %entry
%1 = and i32 %asmresult5.i, 1610612736
%2 = icmp eq i32 %1, 1610612736
br i1 %2, label %if.then7, label %return
land.lhs.true: ; preds = %entry
%1 = tail call { i32, i32 } asm sideeffect ".byte 0x0f, 0x01, 0xd0", "={ax},={dx},{cx},~{dirflag},~{fpsr},~{flags}"(i32 0) nounwind
%asmresult.i25 = extractvalue { i32, i32 } %1, 0
%and.i = and i32 %asmresult.i25, 6
%cmp.i = icmp eq i32 %and.i, 6
br i1 %cmp.i, label %if.then, label %if.else14
if.then7: ; preds = %if.then
%3 = tail call { i32, i32, i32, i32 } asm sideeffect "xchg$(l$)\09$(%$)ebx, $1\0A\09cpuid\0A\09xchg$(l$)\09$(%$)ebx, $1\0A\09", "={ax},=r,={cx},={dx},0,2,~{dirflag},~{fpsr},~{flags}"(i32 7, i32 0) nounwind
%asmresult4.i28 = extractvalue { i32, i32, i32, i32 } %3, 1
%and10 = lshr i32 %asmresult4.i28, 5
%4 = and i32 %and10, 1
%5 = add i32 %4, 3
if.then: ; preds = %land.lhs.true
%2 = and i32 %asmresult5.i, 1610612736
%3 = icmp eq i32 %2, 1610612736
br i1 %3, label %if.then8, label %return
if.then8: ; preds = %if.then
%4 = tail call { i32, i32, i32, i32 } asm sideeffect "xchg$(l$)\09$(%$)ebx, $1\0A\09cpuid\0A\09xchg$(l$)\09$(%$)ebx, $1\0A\09", "={ax},=r,={cx},={dx},0,2,~{dirflag},~{fpsr},~{flags}"(i32 7, i32 0) nounwind
%asmresult4.i30 = extractvalue { i32, i32, i32, i32 } %4, 1
%and11 = lshr i32 %asmresult4.i30, 5
%5 = and i32 %and11, 1
%6 = add i32 %5, 3
br label %return
if.else13: ; preds = %entry
%and15 = and i32 %asmresult5.i, 524288
%cmp16 = icmp eq i32 %and15, 0
br i1 %cmp16, label %if.else18, label %return
if.else14: ; preds = %land.lhs.true, %entry
%and16 = and i32 %asmresult5.i, 524288
%cmp17 = icmp eq i32 %and16, 0
br i1 %cmp17, label %if.else19, label %return
if.else18: ; preds = %if.else13
%and20 = and i32 %asmresult6.i, 67108864
%cmp21 = icmp eq i32 %and20, 0
br i1 %cmp21, label %if.else23, label %return
if.else19: ; preds = %if.else14
%and21 = and i32 %asmresult6.i, 67108864
%cmp22 = icmp eq i32 %and21, 0
br i1 %cmp22, label %if.else24, label %return
if.else23: ; preds = %if.else18
if.else24: ; preds = %if.else19
tail call void @abort() noreturn nounwind
unreachable
return: ; preds = %if.else18, %if.else13, %if.then7, %if.then
%retval.0 = phi i32 [ %5, %if.then7 ], [ 2, %if.then ], [ 1, %if.else13 ], [ 0, %if.else18 ]
return: ; preds = %if.else19, %if.else14, %if.then8, %if.then
%retval.0 = phi i32 [ %6, %if.then8 ], [ 2, %if.then ], [ 1, %if.else14 ], [ 0, %if.else19 ]
ret i32 %retval.0
}
declare void @abort() noreturn nounwind
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; This function is called by each of the dispatch functions we generate;
;; it sets @__system_best_isa if it is unset.