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author | Evan Cheng <evan.cheng@apple.com> | 2010-11-30 23:55:39 +0000 |
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committer | Evan Cheng <evan.cheng@apple.com> | 2010-11-30 23:55:39 +0000 |
commit | 3d2125c9dbac695c93f42c0f59fd040e413fd711 (patch) | |
tree | 1f7e426fb325a457b03fafbc84f4f6446af3c270 /lib/Target/X86/README.txt | |
parent | 3f8c110dc643847363686d543a56c23c41353ab0 (diff) | |
download | external_llvm-3d2125c9dbac695c93f42c0f59fd040e413fd711.zip external_llvm-3d2125c9dbac695c93f42c0f59fd040e413fd711.tar.gz external_llvm-3d2125c9dbac695c93f42c0f59fd040e413fd711.tar.bz2 |
Enable sibling call optimization of libcalls which are expanded during
legalization time. Since at legalization time there is no mapping from
SDNode back to the corresponding LLVM instruction and the return
SDNode is target specific, this requires a target hook to check for
eligibility. Only x86 and ARM support this form of sibcall optimization
right now.
rdar://8707777
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120501 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/X86/README.txt')
-rw-r--r-- | lib/Target/X86/README.txt | 18 |
1 files changed, 0 insertions, 18 deletions
diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt index e67fab1..a305ae6 100644 --- a/lib/Target/X86/README.txt +++ b/lib/Target/X86/README.txt @@ -895,24 +895,6 @@ compare: //===---------------------------------------------------------------------===// -Linux is missing some basic tail call support: - -#include <math.h> -double foo(double a) { return sin(a); } - -This compiles into this on x86-64 Linux (but not darwin): -foo: - subq $8, %rsp - call sin - addq $8, %rsp - ret -vs: - -foo: - jmp sin - -//===---------------------------------------------------------------------===// - Tail call optimization improvements: Tail call optimization currently pushes all arguments on the top of the stack (their normal place for non-tail call optimized calls) that source from the callers arguments |