Commit Graph

8 Commits

Author SHA1 Message Date
Serge Pavlov b36d214bed [X86] Add description of FXAM instruction
Previously this instruction could be used only in assembler. This change
makes it available for compiler also. Scheduling information was copied
from FTST instruction, hopefully this can be a satisfactory approximation.

Differential Revision: https://reviews.llvm.org/D104853
2021-06-25 12:26:51 +07:00
Craig Topper 31c40f2d6b [X86] Add mayLoad/mayStore flags to some X87 instructions that don't have isel patterns to infer them from.
Should remove part of the differences in D81833 due to some
some of these getting isel patterns.
2020-06-23 23:40:30 -07:00
Craig Topper bf7593ec4a [X86] Print all register forms of x87 fadd/fsub/fdiv/fmul as having two arguments where on is %st.
All of these instructions consume one encoded register and the other register is %st. They either write the result to %st or the encoded register. Previously we printed both arguments when the encoded register was written. And we printed one argument when the result was written to %st. For the stack popping forms the encoded register is always the destination and we didn't print both operands. This was inconsistent with gcc and objdump and just makes the output assembly code harder to read.

This patch changes things to always print both operands making us consistent with gcc and objdump. The parser should still be able to handle the single register forms just as it did before. This also matches the GNU assembler behavior.

llvm-svn: 353061
2019-02-04 17:28:18 +00:00
Craig Topper 7a2944efe1 [X86] Print %st(0) as %st when its implicit to the instruction. Continue printing it as %st(0) when its encoded in the instruction.
This is a step back from the change I made in r352985. This appears to be more consistent with gcc and objdump behavior.

llvm-svn: 353015
2019-02-04 04:15:10 +00:00
Craig Topper f77b858dc3 Revert r352985 "[X86] Print %st(0) as %st to match what gcc inline asm uses as the clobber name to make MS inline asm work correctly"
Looking into gcc and objdump behavior more this was overly aggressive. If the register is encoded in the instruction we should print %st(0), if its implicit we should print %st.

I'll be making a more directed change in a future patch.

llvm-svn: 353013
2019-02-04 04:15:02 +00:00
Craig Topper 5a570dd437 [X86] Print %st(0) as %st to match what gcc inline asm uses as the clobber name to make MS inline asm work correctly
Summary:
When calculating clobbers for MS style inline assembly we fail if the asm clobbers stack top because we print st(0) and try to pass it through the gcc register name check. This was found with when I attempted to make a emms/femms clobber all ST registers. If you use emms/femms in MS inline asm we would try to use st(0) as the clobber name but clang would think that wasn't a valid clobber name.

This also matches what objdump disassembly prints. It's also what is printed by gcc -S.

Reviewers: RKSimon, rnk, efriedma, spatel, andreadb, lebedev.ri

Reviewed By: rnk

Subscribers: eraman, gbedwell, lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D57621

llvm-svn: 352985
2019-02-03 07:53:39 +00:00
Andrea Di Biagio d2e2c053cf [llvm-mca] Use a different character to flag instructions with side-effects in the Instruction Info View. NFC
This makes easier to identify changes in the instruction info flags.  It also
helps spotting potential regressions similar to the one recently introduced at
r336728.

Using the same character to mark MayLoad/MayStore/HasSideEffects is problematic
for llvm-lit. When pattern matching substrings, llvm-lit consumes tabs and
spaces. A change in position of the flag marker may not trigger a test failure.

This patch only changes the character used for flag `hasSideEffects`. The reason
why I didn't touch other flags is because I want to avoid spamming the mailing
because of the massive diff due to the numerous tests affected by this change.

In future, each instruction flag should be associated with a different character
in the Instruction Info View.

llvm-svn: 336797
2018-07-11 12:44:44 +00:00
Simon Pilgrim f5ecd8d50d [llvm-mca][x86] Add Generic cpu resource tests
Added a Generic x86 cpu set of resource tests to allow us to check all ISAs.

We currently use SandyBridge as our generic CPU model, but it's better if we actually duplicate these tests for if/when we change the model, it also means we don't end up polluting the SandyBridge folder with tests for ISAs it doesn't support.

llvm-svn: 334853
2018-06-15 18:35:25 +00:00